UDAYA English Medium High SCHOOL Std - X - Uday Pre ...

UDAYA English Medium High SCHOOL Std - X THE LIVING WORLD Plant and animal exhibit considerable diversity ot the cellular level. During the evolution of organism, diversity has occurred in the structure and functions of the cells. The higher algae like kelp and Sargassum are Multi Cellular. Plants are deep routed and widely branched. They have longer life span and show diversity in reproduction. According to modern classification plants and animals are classified into five major kingdoms. KINGDOMS Monera

Protista

1)Bacteria

Mycota

Metaphyta

Metazoa

1)Unicelluar 1)Fungi

Nonvascular

Multi cellular

Algae

plants

2)Blue

1)Multicellular

Green Algae

Algae 2)protozoa

a)Red algae

1)Animals

Porifera

b)Brown Algae

2)Coelenterata

c)Green Algae

3)platyhelmirithes

2)Bryophytes

4)Aschelmithes

a)Vascularplant 5)Annelida 1)Pteridophytes 6)Arthropoda 2)Gymno Sperms 7)Mollusca 3)Angio Sperms 8) Echiniodermata Chordata 1)Pisces 2)Amphibia 3)Reptilia 4)Aves 5)Mammalia

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UDAYA English Medium High SCHOOL Std - X MULTI CELLULAR ALGAE Most of the algae are multicellular and have a flat plant bodies called Thallus. These algae are non- vascular plants. They are classified into three group’s:Red Algae – Batra chospermum, polysiphonia Brown Algae - Sargassum Ecto carpus. Green ALGAE – Spirogyra ulothrix. Rocks, corals and other plants of the ocean. Members of green algae are mostly fresh water forms found in ditches, pounds lakes and rivers Algae are capable of carrying out photo synthesis. Green Algae contain the green pigment called chlorophyll. In red Algae chlorophyll ‘a’ and ‘b’ pigments are foundin addition a red pigment called phycoery thrin and a blue pigment called phycolyanin are found. Hence the plant body show red colour. In brown Algae chlorophyll ‘a’ and ‘c’ pigments are found. In addition xanthohyll pigments are found in aboundance. Hence these Algae are brown in colour. The cell wall of Algae is composed of cellulse and pectin. Usually the cells are uninucleated reproduction takes place both by sexual and a sexual means. Sexual reproduction takes place by the fusion of male and female gametes A sexual reproduction takes place by the production of spores. BRYOPHYTA These plants are found both on moist land and in water. Hence, they are commonly called as amphibians of the plant kingdom. Bryophytes are multicellular plants having the features of eukaryotes. The plant body is a flattened, thalloid structure and can be differentiated into stem, lives and rhizoids. In these plants root-like structure called rhizoids are present. Some plants of this group grow horizontally in the soil some plants grow vertical to the soil surface. The life cycle of bryophytes includes two successive generation called gametophyte and sporophyte. Gameto phytes are gamete producing plants. Sporophytes are spore producing plants and are prominent and larger in size and manufacture food with the help of chloroplast. Sporophytes are smaller in size and depends on gametophytes for food. They reproduce by sexual and vegetative methods. PTERIDOPHYTA Pteridophytes are included in the group called tracheophytes because they have the vascular tissue to conduct water and mineral salts the plant body is differentiated into rod, stem & leaves. There are two generations in the life cycle namely sporophyte and gametophyte. Sexual reproduction involved the fusion of male and female gametes.

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UDAYA English Medium High SCHOOL Std - X GYMNOSPERMS Gymnosperms are a group of seed – bearing vascular plants. They grow in dry but cold climate regions. These are perennial and evergreen plants. The vascular system is well developed with xylem and phloem. The most prominent feature is the production of two kind of spores namely micro-spores and megaspores they were reduced in structure called micro sporophylls and megasporophylls. They produce multicellular structure called cones. They are of two types namely male and female cones. Sexual reproduction involves the fusion of these cells to form a zygote. ANGIOSPERMS Angiosperms are the most evolved among plants. in these plants, the seeds are enclosed in a structure called fruit. Angiosperms are commonly called as flowering plants vascular tissues are well developed. Flowers are the reproductive organs. A special branch bearing a cluster of flowers is called in florescence. Seeds are produced in flowers seeds are of two types. 1) Mono cotyledonous 2) dicotyledonous monocot plants have fibrous root system culture. Dicot plants have tap root system. In fibrous, roots develop from the base of the stem and branch profusely. A single main or central root is absent. In taproot system, the primary root from the radical of the seed grows to become the main or central part of the root system. It produces many secondary and tertiary branches. VERTEBRATES Vertebrates represent a major group among the advanced animals called chordates. chordates exhibit the following characteristic features 1. Presence of a solid supporting structure on the dorsal side of the body called notochord. presence of a dorsal tubular nerve cord. Vertebrates are characterized by the presence of a backbone or vertebral column. The skeletal system consists of hard rigid structures called bones which proude support to the body. The body is divided into head trunk and limbs. Digestive system consists of mouth, pharynx, oesophagus stomach intestine and many associated glands. Respiratory organs are well developed. They are in the form of gills in aquatic forms and lungs in terrestrial forms. Heart is ventral in position and is chambered. Excretory organs are in the form of a pair of kidneys Nervous systems consists of dorsal tubular nerve cord which becomes differentiated into brain and spinal cord. Vertebrates are unisexual only sexual reproduction is seen. Vertebrates is grouped into the following 5 types: 1. Pisces 2. Amphibians 3. Reptilians 4. Aves 5. Mammalians

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UDAYA English Medium High SCHOOL Std - X PIECES (FISHES) Fishes are equality vertebrates with streamlined body skin is covered with scales which provide protection skin contains mucous glands. Locomotory structure are in the form of paired and unpaired fins help in balancing. Digestive system is well developed with an alimentary canal associated glands. Respiration is typically by pharyngeal gills. Heart is two chambered Fishes are cold blooded animals Nervous system is well developed with brain and spinal cord. Internal skeleton is either cartilaginous or bony these are unisexual animals they reproduce sexually. AMPHIBIANS They are adapted living successful, on both land and in water. The body is divided into head, trunk and limbs. The skin is very soft and moist due to secretion of mucous glands, mouth is provided with jaw. Nostrils are exposed above the mouth. Fore limbs have four digits while hind limbs have five digits each. It has well developed digestive system with alimentary canal and associated glands. Respiration is by gills and skin, Buccal cavities and lungs. A three chambered heart is found. These are cold blooded animals nervous system is well developed with a brain, and spinal cord. These are unisexual animals. They reproduce sexually fertilization is external. Thus lay eggs on stagnant water metamorphosis are seen in the life cycle of these animals. REPTILIANS These are the first terrestrial vertebrates. They have an elongated body covered by a dry skin bearing an exoskeleton of horny scales. Both fore limbs and hind limbs have five digits each some of the reptiles like snakes are limbless. Digestive system very well developed Respiration takes place through lungs the heart is three chambered. These are cold blooded animals-nervous system consists of a brain a spinal-cord these are unisexual animals. They reproduce by sexual methods. All reptiles are egg laying animals. AVES The body is covered by feathers. Feathers are diversified with various colours. In birds fore limbs are modified into wings which help in fight the body is very light and the bird can fly without friction the bones are holly light and filled with air such bones are called pneumatic bones. Bones are specialized for storing excess air. A four chambered heart is present birds are active warm blooded animals. Nervous system is more evolved than in reptiles. Birds are unisexual reproduction by sexual methods. All are oviparous and eggs covered by calcareous shells. MAMMALIANS These are the most evolved animals in the animal kingdom. The skin is covered by hairs mouth is provided by jaws bearing teeth. The eye have movable eyelids and eyelashes. Ear has a fleshy external pinna. Limbs are pentadactyl ending in claws or nails Respiration takes place through lungs. The heart is four chambered with two auricles and two ventricles the nervous system consists of brain spinal cord, cranial and spinal nerves. 4

UDAYA English Medium High SCHOOL Std - X These are unisexual animals reproduce by sexual methods most mammals give birth to young ones except echidna and platypus. They are egg laying mammals.

Unit :- 2 THT STUDY OF CELLS ANIMAL TISSUE Animal tissue are more complex in nature. They consists of four main types of tissues they are:1) Epithelial tissue 2) Muscular tissue 3) Connective tissue 4) nervous tissue EPITHELIAL TISSUE This tissue is the outer covering of the body, also the inner wall of the body is lined with this tissue. The epithelial tissue consists of a single layer of cells called “Simple epithelium”. If this tissue consists more then one layer, then it is called “Stratified epithelium”. Simple epithelium consisting of flat plate like cells is called “ squamous Epithelium” is found in the aleveoli of lung and in esophagus, in blood vessels blood capillaries and chambers of the heart . this tissue is referred to as endothelium permits materials to diffuse through it. The epithelial tissue containing elongated cells is called “columnar epithelium”. The columnar epithelium is found in the layer of the stomach. It is also found in the inner layer of small intestine, pharynx, larynx and oviducts the mucus secreted by the cells in the stomach prevents the wall of the stomach from acidic contents and digestive enzymes. The epithelium bearing numerous cilia is called “ ciliated epithelium”. Epithelium consisting of cube shaped cell is known as ‘Cuboidal Epithelium. This epithelium forms the lining of many ducts such as pancreatic duct, salivary and sweat duct this epithelium is involved in secretion of glands like salivary glands and thyroid glands. FUNCTIONS OF EPITHELIAL TISSUES 1. The epithelium forms a thick tough barrier and protects the underlying tissues in the form of external skin. 2. The ciliated epithelium helps in the movement of materials. 3. The epithelium cells in glands facilitate secretion. 4. Epithelium helps in absorption of nutrients and excretion. 5. The epithelium in sense organs contain receptor cells.

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UDAYA English Medium High SCHOOL Std - X MUSCULAR TISSUE The muscular tissue is made up of muscle cells, which appear like fibres. Hence they are called as “Muscle Fibres”. These fibres are specialized for contraction and relaxation. This property is responsible for movement of limbs and bending of the body. The muscles cause the movement in the internal organs like heart, Stomach and alimentary canal, but they are not under the control of the animals. Hence they are called “Involuntary muscles”. The muscles of outer organs like limbs which are under the control of the animals, are called as “Voluntary Muscles”. The muscular are classified into 3 types based on the structure, function and location. They are :1. Unstriped muscles 2. Striped muscles 3. Cardiac muscles

UNSTRIPED MUSCLES These muscles are made up of spindle shaped elongated muscle fibres without strips. So they are called as “Unstriped muscles”. These muscles are also called as “Smooth muscles”. A number of muscles fibres are held together by a membrane to form bundles called “Muscles”. This muscle helps the peristaltic movements of esophagus, intestine and stomach. These muscles are found in the cavity.

STRIPED MUSCLES The muscles which are made up of elongated unbranched cylindrical fibres with striations are called “STRIPED MUSCLES”. These muscles are usually attached to bones.

CARDIAC MUSCLES The heart is made up of special type of muscles called “Cardiac Muscles”. The muscles are stripes and branched.

CONNECTIVE TISSUE The tissue which connects various other tissues of the body and provides support is called “Connective tissue”. these tissues occur in all the body parts. These tissues basically consist of cells and fibres enclosed in a ground substances. matrix is formed by the non living things like fibres and other materials which surround the living cells. Connective tissue are classified into 3 groups according to the state of Matrix. They are : 6

UDAYA English Medium High SCHOOL Std - X 1) Loose connective tissue 2) Dense connective tissue 3) Fluid connective tissue

LOOSE CONNECTIVE TISSUE The tissue in which the fibres in the matrix are loosely arranged is called "Loose Connective Tissue".

AREOLAR TISSUE This tissue is found below the skin. the fibres are loosely connected with one another. air spaces are found in between the fibres. hence it is called as Areolar Tissue.

ADIPOSE TISSUE This tissue consists of closely packed fat cells. the cell are surrounded by fine reticular fibres. these tissues provide insulation against cold and protect the body like a shock absorber.

RETICULAR TISSUE These tissues provide frame work for important organs like liver, spleen, bone marrow, tonsils and mucous membrane living the respiratory track and alimentary canal. It consists of reticular fibres.

TENDONS AND LIGAMENTS Tendons attach the muscles to the Bones. Ligament consists of elastic fibers. They connect one bone to another. They help in movement of bones.

Dense Connective Tissue The tissue consists of hard materials are called "Dense connective tissue" Dense connective tissue are of 2 types. They are 1. Cartilage 2. Bone

Fluid Connective Tissue The blood and lymph are called the liquid connective tissue of the body. They have a fluid matrix.

Blood Tissue The fluid matrix of the blood is called plasma. The RBC, WBC and plate lets are found floating in it. The red blood cells are involved in supplying oxygen to every cell in the body. They also remove carbon dioxide from the cells and transport it to lungs. 7

UDAYA English Medium High SCHOOL Std - X The white blood cells help in body defense.

Lymph Tissue Lymph is nothing but blood without RBC’s

Nervous Tissue The nervous tissue responds to external and internal stimuli of the body. This tissue transmits nerve impulses from all parts of the body to nerve centres very quickly and bring back the response.

LIFE PROCESS The higher living organs are more complicated compared to the lower organism. They are unique in their characteristics because they can perform different activities within their bodies., thus helping the life to go on such activities are nothing but life process.

LIFE PROCESS: The difference between process or activities going within the living organisms carried out by specific organs in the body are called as life process. Example: Digestion, excretion, respiration etc.

Stimulus: The change in our surrounding is called stimulus.

Response: The reaction of the body to the changes around us. Ex: 1) Seeing a snake is stimulus running away from it is response. 1) Touching some substance is stimulus the itching of the snake is response. The response and stimulus is carried out by the nervous system which contains the receptors, effectors of conductors.

NERVOUS SYSTEM Receptor Organs which receives Stimulus.

Effectors Organs which response To the stimulus.

Ex- Sense organs

Ex: Muscles

Conductor Organs which Connected the Receptors. Ex: Nerves

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UDAYA English Medium High SCHOOL Std - X HUMAN NERVES SYSTEM It consists of mainly a highly developed brain and spinal cord and many nerves associated with them. Due to the greater capacity of the brain and its highly developed in man.

Brian Fore

Cerebrum

Cortex

Mid

Diencephelon

Medulla

Thalmus

Hind

Pons varoli

Hypothalmus

Cerebellum

Medulla ablongata

FORE BRAIN: a) Cerebrum: it is the largest part of the brain, which individuals into two halves called as right cerebral hemisphere and left cerebral hemisphere. 1. Right cerebral hemisphere controls the organs on the left side through the nerves and vice versa. This cerebrum can be divided in to outer cortex and inner medulla. 2. The outer cortex is made up of many fold separated by grooves in order to increase the surface area. 3. The outer cortex is composed of cytons, which form the thin gray matter and the inner medulla is more massive, which is white in color. It also contains many nerves fibrous. 1. Motor Area: Controls the movement of voluntary muscle. 2. Sensory Area: This helps to interrupt the impulse coming from the sense organ. Associated area: It helps in memory, reasoning, judgement, concentration, planning, problem solving, speech, and expression of through etc. Therefore the Cerebrum is the center for different mental activities. CENTRAL NERVOUS SYSTEM 1. It contains of brain and the spinal cord. 2. Hindbrain continues as the spinal cord both these parts are covered by three think membrane called as cebrospindal fluid (CSF). 3. Circulating between these membrane is called the outer durameter, the middle layer is Arachnid, the inner most layer is called the piameter. 4. The fluid gives protection and provides nutrients to the brain and spinal cord. The brain is protected by a bony case, called the Cranium. (Scull) If the part of the brain which belong to the cerebrum and above the mid brain 9

UDAYA English Medium High SCHOOL Std - X 1) It connects the cerebrum. It can be divided into the upper thalamus and bones by hypothalamus. 2) The thalamus is the ready station for the all sensory impulses and sends them to appropriated region of the cortex for interpretation.

MID BRAIN  

It is small region located between diencephalon and pons navoli [i.e. it is connecting region between the cerebrum and medulla oblongata] It act a center to send the message from the hind brain to the fore brain It act as a center for receiving impulse from the eyes and ears.

HIND BRAIN a) Pons Varolli: 1) It is between the cerebrum and medulla oblongata. The fibers in this region connect the two nerves of the cerebrum. 2) It is center for controlling facial expressions, respiration, chewing etc. four pairs of cranial nerves start from the pons varolli. b) Cerebellum: 1) It is the second largest part of the brain which is behind and below the cerebrum. 2) It is divided in to two valves, separated by grooves and appears like a butterfly. 3) It is a center for controlling the voluntary muscles, maintains the body equilibrium and fortune of the body during running, walking, etc. c) Medulla Oblongata: 1) It is the base of the brain which continuous as the spinal cord. 2) It contains the center for voluntary activities like breathing, heartbeat, blood pressure, sneezing, and coughing etc.

SPINAL CORD It is long cylindrical slightly flattened tube like structure, running through out the vertebral column, whose length varies from 42 cm to 45 cm in an adult. 1. 2. 3. 4. 5. 6. 7.

Posterior (dorsal) gray horn (sensory ) Dorsal root Central canal Spinal nerves Ventral root White matter Anterior gray horn (motor)

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UDAYA English Medium High SCHOOL Std - X 1. It is slightly flattened cylindrical structure. Which runs throughout the vertebral column. 2. It is surrounded by 3 layers, which contains CSF flowing though these. 3. The spinal cord is made up of the gray matter and it resembles the shape of the butterfly with the wings outspread. 4. The upper wings are called posterior gray horn, the lower wings are called anterior gray horns. It conducts sensory, impulses from part of the body outside the body nervous system to the brain and conducts motor impulses from the brain to the other parts of the body. 1. It is a centre for many reflex actions (response to stimuli) Receptor Action: It is a sudden – response (reaction) to an external stimulus, which is independent of the brain. Such actions are carried out by the spinal cord. Ex : We withdraw out hand when we touch any hot body. Reflex Area: It is the path travelled by the nerve impulse involved in reflex action. PARTS OF REFLEX ACTION: 1. Receptor (Sense organ): Receives the stimulus. 2. Sensory Neuron: transfers the impulse (message) from the receptor to the spinal cord (hind brain ). 2. Associated Neuron: Transfers the message to the motor neuron. 3. Motor Neuron: Transfers the message to effector. 4. Effector (Muscle of glands): Reacts or responds to the stimulus.

PERPERIPHERAL NERVOUS SYSTEM 1.

Cranial Nerves: a) These nerves originates from the brain and link to the other parts of the body. b) 12 pairs of cranial nerves c) May be i) Sensory nerves: Carry impulses from other parts of the body to the brain. ii) Motor nerves: carry impulses from brain to the other body parts. iii) Mixed Nerves: carry (impulses by) both types of messages (sensory or motor). 11

UDAYA English Medium High SCHOOL Std - X 2.

Spinal nerves: a) originates from the spinal cord and connect to other body parts. b) 31 pairs of spinal nerves. c) mixed nerves (Sensory or motor)

AUTONOMIC NERVOUS SYSTEM 1. It is type of nervous system in which the nerves work independently without our will. 2. They contain special type of nerves called sympathetic nerves and parasympathetic nerves, whose action is opposite to each other. Ex : The contraction of the muscles in the lungs is performed by sympathetic nerves and the relaxation of the muscles is done by parasympathetic nerves. These nerves connect many internal organ like heart, lungs etc.

SENSE ORGANS They are the organs, which can sense the changes around us or the stimulus and help us to sense different objects around us. Whenever the sense organ receives the stimulus the message is sent to the brain where it is interpreted and the information is sent to the receptor which produces and response help to sense the object- there are 5 types1) Eyes, 2) tongue, 3) ears, 4) skin, 5) nose.

1. Eyes: It is a sense organ, which help us to see the object around us, with the help of the light. There are two eyes situated in front of the face and externally there are protected by the follow partsa) Eye ball: These two structures are placed in the bony sockets in front of the face. b) Eye brose: the line of hair above the eyes, which protect the eye from dust particles falling from above. c) Eye laid: the movable lids, which protect the eye from and regulate the dust particles. 12

UDAYA English Medium High SCHOOL Std - X d) Eye lashes: the hair lining of the eyelids are called the eye lashes, which protect the eye from minute dust particles. e) Lacrimal glands: (Tear glands ) Which produces some watery secretions called as tears. They help in removing in the dust particles and keep the eye moist. They mainly consist of 3 layers. Namely the 1) Sclera, 2) Choroid, 3) Retina. 1. Sclera: it is outer most layer, which is white in colour. The front portion of the sclera is transparent and bulged which is called cornea. The cornea is protected by the membrance called conjunctiva. 2. Choroid: it is the middle layer, which contain many layers and blood vessels. The front part of the choroid at the center is bulged which is called pupil. The pupil is held by the spinal type of tissue called the Irish. 3. Retina: it is inner most layer of the eye. It has many cells like the rod and cones and (these identify color ) some part of the retina is depressed at the centre behind the lens called the forea where the internal image is formed and some of the other part of the retina bundle of nerve fibrous called the optic nerve leaves the eye and connects to the brain. The part of the retina is called the blind spot due to the absence of cones and rods. The region between the lens and the retina is filled with thick fluid called ritereous.

Defects of the eye working The light reflected by the objects strikes the lens through the cornea. The incident rays get refracted and connect the phobia reflecting.

POLLUTION Environmental pollution: it is defined as the unwanted change in the physical, chemical and biological changes of the environment. These changes mainlytake place due to many human activities. Pollution: The substances, which cause undesirable change in the environment are called pollutants or contaminants. Types of pollutions: a) Biodegradble Pollutants: these can be converted into harmless form by diluting it or by action of bacteria. Eg: Sewage treatment by bacteria SO2 can be diluted in water. b) Non biodegradable Pollutants: these cant be converted in to harmless form but cause biomagnifications. EG: lead vapours, DDT etc.

Types of Pollutants: 1) Air Pollution 2) Water Pollution 3) Soil Pollution 13

UDAYA English Medium High SCHOOL Std - X MICRO ORGANISMS       

Infectious Diseases. Characteristics of diseases (Symptoms). Mode of infection. Agencies carrying Pathogen. Preventive Measures. AIDS. Hepatitis B and Jaundice.

The study of living organisms is called Biology, which includes plants, animals, micro-organisms. Micro organisms are a type of minute organisms which can be seen easily through a micro scope. There are different types of micro organisms like bacteria, virus fungi, protozoans, algae etc. these organisms are both useful and harmful. They are harmful because of following uses:1. 2. 3. 4. 5. 6. 7. 8.

Fermentation of cuds, idli and dosa paste. In the treatment of oil sils and industries. It is used in nitrogen fixation. It is used in medicine and food. It is used in tanning of leather. They are used as food and enzymes. They are to make soil fertile. They are also used in metallurgical process.

Pathogens:- Diseases causing micro organisms are called Pathogens. Disease:- long term are called diseases which generally need more time for cure. Depending on the various causes for the diseases the factors can be divided into two Factors categories.

Intrinsic factors (Internal) 1. Malfunctioning of body parts 2. Genetic disorders 3. Hormonal imbalance 4. Defective immune system

Extrinsic factors (external) 1. Malnutrition 2. Micro- organisams 3. Bad habits 4. Pollunts

Hereditary Congenital

Malfunctioning of body parts

The factors which exist within the human body causing many diseases are intrinsic factor. The Sudden accident diseases cause by these factors are called organic diseases or metabolic diseases. Eg:- Heart attack, Kidney failure, Diabetes, cataract etc. 14

UDAYA English Medium High SCHOOL Std - X

The factors which exists outside our body and cause diseases are called Extrinsic factors. Eg:- Goiter, cholera, Malaria, Tetanus etc. Intrinsic factors : Malfunctioning of body parts

Hereditary

Congential

Sudden accident

The improper functioning of the body parts leading to various may be due to the above factors.

1 Hereditary:- These defects are passed to the individual from the parent. Eg:- Biabetes, hemophilia, Myophia, Epilepsy

2 Congential:- Defective parts in birth or mental retardation. Eg:- deafness, Blindness. Etc.

3 Sudden Accident:- sudden cardiac failure, damaged bones, certain cancers because of exposer to harmful radiation.

VIRAL DISEASES: (diseases caused by virus) I Aids:- Acquired immunity deficiency syndrome. It is caused by the virus HIV (Human Immune deficiency Virus) it is a highly infectious diseases, when destroys the immune system of the body. A person suffering from AIDS is easily prone to any common infections or disease resulting in the death of the person.

Causes:HIV enters a healthy body through any of the following means 1. Sexual contact with an infected person (increasingly seen in homosexuals or people practicing ``multisexuality) 2. By receiving infected blood. 3. By using an sterilized syringes and needles. 4. From the infected mother to the child through the placentra, during the birth of a baby or feeding the baby. 15

UDAYA English Medium High SCHOOL Std - X This mainly due to lack of knowledge about AIDS and lack of education.

Symptoms:A,

Intial Symptoms 1. 2. 3. 4. 5. 6.

Comman cold and fever. Mouth ulcers. Head ache. pain in the joints. throat pain. itching of skin, rashes on the skin etc.

1. 2. 3. 4. 5. 6. 7.

Long term fever and body ache. Sweating during nights. loss of weight . Loss of immunity. Itching of the skin, burning in the throat, cough and internal ulcers. White patches in the mouth. Loss of memory power.

C. Secondary Infection 1. Giddiness. 2. Diarrohea 3. Fever, head ache 4. Infected endocrine glands.

Common dieases in AIDS patients 1. Tuberculosis 2. Pneumonia 3. Skin Cancer 4. Brain Fever.

Remedies :1. Use sterilized and disposable syringes and needles. 2. HIV test before blood transfusion. 3. Practice safe sex 4. Stop the intake of drugs. 5. Educate the public about the disease. 6. Infected mother should not breast feed her child. 16

UDAYA English Medium High SCHOOL Std - X Structure of HIV :-

A HIV Is spherical in shape with RNA at the centre to which are attached certain type of enzymes these enzymes along with the RNA are surrounded by a protein layer. Next to the protein coating there is a double layer of fatty with the help of the enzymes RNA produces DNA. Working of HIV in a healthy body:When the HIV enters the healthy cell it produces new DNA. Due to this HIV cannot be identified by the host, slowly the HIV becomes stronger and dominant. The white blood cells are not produced in adequate amounts and they don’t attack the virus. Due to this virus destroyes the immune system and the person is easily prone to many diseases till his end (death). Plasma. The virus that cause hepatitis B is HBV (Hepatitis B Virus )

Causes :1. Sexual contacts. 2. Unsterlized syringes and needles 3. Drug addiction. 4. From the infected mother to the baby. 5. Infected blood transfusions. 6. Using infected surgical instruments. 7. By following acupuncture.

Symptoms: 1. Mild fever, cough, cold. 2. Throat infections. 3. Vomitting. 4. Loss of appetite. 5. Stomach ache. 6. The eyes, skin, nails, urine etc become yellow. 7. weakness, body ache etc.

Remedies:1. Take vaccination. 17

UDAYA English Medium High SCHOOL Std - X 2. Stop consuming contaminates food and water. 3. Use sterilized and disposable syringes and needles. 4. Practice safe sex. 5. Stop the intake of drugs. 6. Educate the public about the disease. 7. Infected mother should not breast feed her child.

Mechanisam of virus in a healthy body:As the virus gain the enter into a healthy body the pigment present in the RBC is destroyed in the liver. The liver cells get damaged bilirubin is not transported uniformly but goes on accumulating in the blood due to this the colour of the skin, eye nails, urine etc., change.

Types of Hepatitis: 1. Hepatitis A, B, C, D, E, F and G. 2. Hepatitis B is a deadly disease, which can cause liver cancer and leds to the dearth of the person within a very short period.

ROCKETS AND ARTIFICIAL SATELLITES Through the development of science and technology , man has been able to explore the different objects in the space and many places on the earth. This age in which we are living is called “THE SPACE AGE”. The uses of space age are : 1) 2) 3) 4) 5)

Helps in communication thus linking different parts of the world. Helps to explore the space. The exploration of the solar system. To predict the weather conditions. To study the earth resources, remote sensing terrain mapping and studying the earth on the whole. 6) In military operations.

It was possible to explore the different objects mainly due to the development of rockets. The persons who took great effort to design such rockets were Robert Goddard in USA and Konstantin Tsiolkovsky in Russia. These two persons developed some powerful machines, which could move in the earth’s orbit and to the outer space. These powerful machines were 18

UDAYA English Medium High SCHOOL Std - X called as rockets. They could carry satellites, spacecrafts and also human begins into the space.

Rocket:

A rocket is a device used to launch a satellite or spacecraft into the space.

Principle of Rockets:They work on the principles of conservation of conservation of momentum i.e., “The total momentum of a system remains constant when the net external forces acting on the system is zero. During firing, the fuel is burnt and pressure is created on its walls. At the sometime the exhaust gases are liberated at greater velocities. Due to these, unbalanced forces (net forces), the rocket moves in a direction opposite to that of exhaust gases.

CONSTRUCTION The four important parts of a rocket are, namely: 1. 2. 3. 4.

The instrument pay load-which contains satellites. The oxidizer tank-which contains an oxidizer necessary for burning the fuel. The fuel which carries an appropriate fuel. The Engine-where the mixture of fuel and oxidizer is burnt to liberate high-speed gases.

Working of a rocket: The fuel and the oxidizer are burnt in the engine to liberate high velocity exhaust gases. These exhaust gases cause the motion of the rocket in a direction opposite to that of the exhaust gases. 19

UDAYA English Medium High SCHOOL Std - X Propellant: The combination of a fuel and an oxidizer is called as a propellant, which may be a solid or a liquid. Eg. Kerosene + liquid-Oxygen

Characteristics of a rocket fuel:1) The fuel should be burnt quickly. 2) It should give out more amounts of exhaust gases, at greater velocities. 3) It should not produce any reminants after combustion.

A Rocket has a characteristic shape. 1. To over come the friction and reduce heating of the system, thus causing easy motion. 2. To give stability to the rocket when it is moving in the earth’s atmosphere. But it can be of any shape, when it is in the space.

Multi-Staged Rockets A combination of a number of rockets is called as multi-staged rockets. It is more advantageous to use multi-staged rockets because of the following reasons. As the rockets moved in the greater velocities, it has to use more amount of fuel to carry such greater quantities of fuel: large space is required which means more amount of weight has to be carried along its journey. But, in a multi-staged rocket, when the fuel has supplied the necessary velocity the first stage is discarded, thus reducing the dead weight. Further, the second stage is discarded and finally, the last stage provides velocity to the spacecraft and falls back.

Equation to Calculate Orbital velocity:-

Let a satellite of mass ‘m’ be moving around the earth in a circular orbit at a height ‘h’ about the ground level. The rocket provides a tangential velocity to the spacecraft. The centripetal force provided by the earth’s gravitation keeps the satellite moving in a circular orbit at a distance of R th from the ground.

According to Newton`s Low of Circular Motion. Fcp=m𝑣 2 R+h

…………Eq ( 1) 20

UDAYA English Medium High SCHOOL Std - X Fcp= GMt m ( R + h)2

…………...Eq(2)

But according to universal law of gravitation :Equating (1) and (2) m𝑣 2 = GMt m ( R+h) ( R + h)2 V0 = GME R+h

V0

GME

𝑅+ℎ

Neglecting `h` because it is small compared to R, then V0=

𝑅𝑔

Where

( g = GME ) R2

V0 ……………… Orbital Velocity ME ………………. Mass of the Earth =5.98 x 1024 kg R ………………. Radius of the Earth = 6.38 x 106 mts G ………………… Gravitational Constant = 6.672 x 10-11 Nm2/kg2 g……………………Gravitational acceleration.

Escape velocity : If the space is to explore any object in the space, it should have sufficient velocity to escape the gravitational pull of the earth. This velocity is called escape velocity, which is nearly 1.4 times the orbital velocity. It is defined as the velocity required by a body to escape the gravitational pull of the earth and thus move in the space. In case of the earth it is nearly 11.2 km/s If a body has to move against gravitational force, work has to be done. The work required to pull of the body out of earth’s attraction is Equal to FMEm 21

UDAYA English Medium High SCHOOL Std - X R If a body is projected with a kinetic, Energy grater rather than this value it escapes into space. 1

mVe2 = 2

𝐺𝑀𝐸𝑚 𝑅

Geostationary Satellites: It is a satellite, which has the same orbital period as the period of rotation of the earth i.e., its orbital period is 24 hours. The type of satellite moves in the same direction as that of the earth due to which it appears to be fixed in its position. To attain that particular period and a fixed orbit the satellite has to be placed at a fixed height from the ground. Such a satellite can cover 1/3 rd of the earth or 3 such satellites are required to cover the entire earth. These satellites are mainly used for communication purpose.

Indian Space Programmes : Indian Space Programme

-

Nov. 21 1963

Indian Space Research Organisation (ISRO)

-

Nov. 1969

First Indian Build Satellite (Rohini RH-75) Single stage

-

Nov. 1967

First Indian Satellite (Aryabhata)

-

April 1975

-

June 1979

-

1988

Orbit (APPLE)

-

1981

First INSAT Launched

-

1982

INSAT -3e Launched

-

Sept. 28 2003

First experimental remote sensing satellite (Bhaskara-1) India’s first large remote sensing satellite Launched (IRS-1A) First Indian satellite to reach geostationary

22

UDAYA English Medium High SCHOOL Std - X GSAT -2 Launched

-

May 8 2003

RESOURCESAT -1 place by PSLV

-

Oct. 17 2003

Abbreviations : ISRO

-

Indian Space research Organisation

IRS

-

Indian Remote Sensing

APPLE

-

ARIANE Passenger pay Load Experiment

SLV

-

Satellite launch Vehicle

ASLV

-

Augmented Satellite Launch Vehicle

PSLV

-

polar Satellite Launch Vehicle

GSLV

-

Geosynchronous Satellite Launch Vehicle

UNIT-7 HEAT Energy is defined as the capacity to-do work .Energy exists in the nature in the different form. Heat is one form of such energy. Heat can be produced by burning substances, from sun, nuclear energy, mechanical work etc. man has been using heat for cooking food, melting of some matter to keep himself warm etc. later on man discovered that heat can be used to mechanical work. Heat Energy:- It is a device where heat energy is used to do useful mechanical work.

Types of Heat Energy:1. External Combustion engine:- it is an engine where the fuel is burnt outside the engine to produce steam, which is made to do mechanical work. Ex: Steam Energy. 2. Internal Combustion Energy:- It is an engine where the energy is provided by burning the fuel inside the engine. Ex: Petrol Engine, Diesel Engine. 23

UDAYA English Medium High SCHOOL Std - X

STEAM ENGINE Diagram:

it is a device where heat energy of the steam is converted into mechanical work. Thomas Savery in 1698 constructed the steam engine . But the modern steam engine is invented by James Watt.

Construction: It consists of a metallic cylendar with a moveable piston in it. The piston is connected to a crankshaft through the piston red. The cylinder is connected to the condenser through the outlet valve, which lets out cold water. The boiler and the condenser are connected through pipes and a pump. Working:

It involves 2 stages namely expansion stoke and exhaust stoke.

a) Expansion stoke water from the condenser is let into the boiler and heated to produce steam. The inlet value is open and the steam is let into the cylinder. The steam under great pressure pushes the piston outward. The piston rotates the crankshaft. b) Exhaust stroke as the piston is sufficiently moved forward the inlet value get closed the steam loses heat and gets condensed. Automatically the exhaust valve opens. The piston is moved inward, which pushes the spent steam out through the exhaust or outlet valve. Expansion stoke and exhaust stoke are repeated in a cycle due to which the linear motion of the piston is converted into circulatory motion of the crankshaft.

Disadvantages of steam engine(External Combustion Engine ) i Due to its bigger boiler it is bulky. ii Non suitable for light vehicles . iii Does not start at once. iv Due to high pressure boiler may burst. v Efficiency is less. vi Produce more pollution. To over come the disadvantages of steam engine, internal combustion engines were invented. These engines were invented by Nicolas otto and Rudolf Diesel.

24

UDAYA English Medium High SCHOOL Std - X Types of I C E a. Petrol Engine: Here petrol is used as a fuel. Developed by Nicolas otto in 1876.

Construction: It consists of a metal cylinder with air light movable piston. Cylinder consists of two openings controlled by intake value and outlet value and a spark plug to produce spark. The piston is connected to the crankshaft through the piston rod. The engine is connected to a carburettor where petrol and air are mixed. Working : This in volves mainly four stages i.e, 1. Intake stoke ( ) (A mixture of petrol (2%) and air (98%) from the carburetor).

2.

As the piston moves downward, low pressure is created and inlet valve opens. A mixture of petrol (2%) and air (98%) from the carburetor are let in. outlet valve remains closed. Compression stroke ( ): After letting in sufficient amount of mixture the inlet valve closes. The piston moves upwards and compresses the mixture to 1/7th its initial volume.

3 Power stoke (Ignirtion Stroke ) : the compressed mixture is ignited by a spark from the spark plug. A large volume of gases and heat is produced. These expand suddenly and pust the piston downward with great force.

4 Exhaust Stoke ( ): When the piston has moved maximum downwards in the power stroke, the exhaust valve opens. Due to the momentum gained by the wheels the piston moves upward and pushes out the burnt gases and water vapor.

25

UDAYA English Medium High SCHOOL Std - X The exhaust valve then closes and the intake valve open. The piston starts moving downward and the steps are again repeated. The to and fro motion of the piston pushes the crankshaft and rotates it rapidly. The initial energy needed to start the cycle is given by self-starter or kick-starter. b Diesel Engine: Diesel or crude office used in a fuel. Diagram and construction same as xxxxxx engine but fuel injection pump is fitted instead of spark plug and there is no carburetor. Working : This also involves 4 strokes. 1. Intake Stroke :- piston moves downward and air alone is let in through inlet valve. 2. Compression Stroke :- Piston moves upward and compresses the air to about 1/17 th of its initial volume. Due to high compression temperature rises to 10000C 3. Power Stroke :- At this stage fine spray of diesel is let us. Due to high temperature the fuel ignites immediately producing large amount of CO, CO2 and water vapor. As a result pressure increases and pushes the piston downward. The hot gases get cooled during expansion. 4. Exhaust stroke:- At this stage the exhaust valve opens and the piston is moved upward, thus pushing out the cool exhaust gases.

Different Between Petrol Engine and Diesel Engine

1 2 3 4 5 6 7 8

Petrol Engine Fuel is petrol Presence of Spark plug and carburetor Suitable for light vehicles Air and petrol mixture is let into the cylinder Compression ratio is less Less smoke is produced Heavy maintenance More efficient

1 2 3 4 5 6 7 8

Diesel Engine Fuel is diesel or crude oil Sparkplug and carburetor are absent Suitable for eheavy vehicles Air and diesel are separately let in High compression ratio. More smoke Less maintenance Less efficient

1 2 3

ECE Fuel is burnt outside Consumes more space and bulky Boiler is present

Different Between I C E and E C E

1 2 3

ICE Fuel is burnt inside the engine Compact and height weight No boiler

26

UDAYA English Medium High SCHOOL Std - X 4 5 6 7 8 9 10

Suitable for light and heavy vehicles More efficient (40%) Less smoke is produced Relatively safe Can be started almost immediately Fuel is diesel or petrol Power is derived from hot gases obtained by combustion.

4 5 6 7 8 9 10

Suitable for heavy vehicles Less efficient (20%) More smoke Unsafe Cannot be started immediately Fel is coal Power is obtained from steam under pressure

UNIT -8 LIGHT Light is a form of energy ,which travels in a medium in the form of wave . It is mentaly Used to see different things arround us. It exibits different properties like refraction ,reflection, interference ,diffraction ,dispertion etc. Dispertion:The phenomenon of splitting of a ray of sunlight into its constituent colours when passed through a glass prism is called dispertion. Sprectrum :The band of colours according to thier wavelenghths due to dispertion is called sprectrum .different colours have different wavelenght and when they pass through the glass prism , the glass has different refrective index, due to which the colour bend to different extents. That is red colour bends very light and violet colour bends the most. Remaining colours orange, yellow, green, blue, indigo bend accordingly. Therefore they split into different colours and bending takes place.

Newton conducted an experiment where he placed another prism in the path of dispersed light. He got The emergent light, which was same as the previous one. Ex:- If a cardboard is placed in the path of the spectrum and a green light is made to pass through the prism, the emergent ray will be green in colour. This shows that no further dispersion takes place from a single colored ray. But white light consists of 7 consitituent colours. The spectrum optained by dispersion of light sometimes doesn’t conatin 7 distinct colours. Red will be overlapping with orange, green will be overlapping with yellow, and blue will be overlapping with indigo. Just like in rainbow 4 colours are visible. Such a spectrum is impure spectrum. Impure spectrum :A spectrum which does not contains all the seven distinct colors, is called an impure spectrum. 27

UDAYA English Medium High SCHOOL Std - X Pure Spectrum:A spectrum, which contains all the 7 distinct colours in their position, is called Pure Spectrum. Spectroscope;It is an instrument used to get a pure spectrum. Construction: It consists of 3 main parts namely i) Collimator:- To produce parallel rays of light. It has slit through light to be analysed enters. It also has a double convex lens, which magnifies and produces parallel rays of light. ii) Prism table - A rotating prism table on which the prism is kept and adjusted to get dispersion. iii) Telescope - It has a double convex lens used to spread the dispersed light distinctly and obtain a pure spectrum on the screen. Spectrometer It is spectroscope used to measure the angle of deviation or angle of reflection. Spectrograph: It is a spectroscope, which consists of a camera instead of eyepiece. Uses of spectroscope : i) Uses to analyze the source of light. ii) To study the nature and amount of elements present in a source. Types of spectrum: 1. Continuous emission spectrum

2. Line emission spectrum

- Hs 7 distinct colours. - Seen in light of sun, arc lamp filament tube or candle. - Sharp, bright lines appear in dark background.

Seen in gases or vapor. Helps to estimate the amount of substance present. Helps to estimate and detect the elements. Helpful in spectrochemical analysis in medicine industry and Criminology. 3. Absorption Spectrum –has a number of dark lines or bands against background of continuous spectrum -seen when composite light passes through semitransparent substance. Some colours here are absorbed. 4. Fraunhofer Lines -Several dark lines due to absorption of certain colours. Seen in solar spectrum, when seen light from a carbon arc lamp is passed through sodium vapor. Used to find hydrogen and Helium in sun. Tyndall and Raleigh discovered that the light passed through the transparent medium get scattered due to the molecules the homogenous medium scatters the light. The frequency and wavelength of the scattered Light is same as the incident light and this is called coherent scattering. With the help of this scattering 28

UDAYA English Medium High SCHOOL Std - X Raleigh could explain blue colour of the sky. When the light passes through the homogenous medium atmosphere blue light get scattered by the molecules. Therefore the sky is blue. The sky is blue therefore the sea (Ocean) water is blue. Raman Effect: C.C. Raman an Indian great scientist was trying to create blue colour of the sky and blue colour of the ocean artificial in the liquids. He discovered Raman’s effect, when through the liquids such as benzene (C6H6 ) and Toluene (C6H5CH3 ) Rth scattered. This effect or phenomenon is called as Raman’s effect. Raman could explain the satisfactory while the change in the music with the help of quantum theory. And raman was awarded Noble Prize. He was the first Indian scientist. The change in the frequency of the scattered light is due to the property of the medium. If you take the spectrum you can findout the molecular structure, so Raman’s effect was applied to solids, liquids, gases and also organic compounds with different source of light. So fast applications of Raman’s effect took place and spectroscope developed.

Unit – 9 SOUND The sound, which has frequency in between 20 Herts to 20,000, is called audible sound. The human ear can hear only the sound waves in this region. If the sound is less than this range then the human hears cannot recognise it properly. Only some animals like dogs, cat & bat cat hear such sonuds. The sound, which has frequency more than 20,000 Hertz are called ultra Sonic sound. The branch of physics, which deals with ultra sonic sound, is called ultra sonics.

There are many applications of ultra sonic sounds. 1. Ultra sonic sounds are used to study the properties of medium. About its elicticity, compressibility and structure. 2. Ultra sonic sounds are used to detect the cracks in the moulds. 3. Ultra sonic sounds are used to make hole in harmful materials for Example: Dentist used the ultra sonic to make bore in the tooth. 4. Ultra sonic sounds are used in welding. 5. Ultra sonic sounds are used in washing machines. 6. Ultra sonic sounds are used to prepare alloys and also mix up two in mixable liquids. The emulsion of the photo film. 29

UDAYA English Medium High SCHOOL Std - X 7. Ultra sonic sounds are used to repel the mosquitoes or they can kill the bacteria. Therefore they are used for sterilization. 8. Ultra sonic sounds are used in SONAR and ultra scanner.

Sonar: SONAR is a device used to detect the object under by sending sonic sound. SONAR is an acronym used for Sound Navigation and Ranging. Sonar Device is fixed in a ship or boat, which sends ultra sonic sound inside the water, and reflected wave are received and the position. And range of the sub marine or any object is determined. So sonar is used to detect the submarine, underwater object and ice burg floating inside the water level.

Ultra Sound Scanner: It is a device used to detect the defect in the sum of the interior of human body by sending ultra sonic sound. ultra sonic sound penetrates through the tissues and when they are reflected back the photograph gives a clear idea about the organs inside the body. They are very important tool to diagnose the disease with the help of ultra sonic sound. They are used to detect the disorder in organ filled with fluids, such as heart, kidney, pancreas, brain, ovary etc. the heart diseases detecting test called E.C.G –Echo Cardio Graph helps to understand the working of the heart. Specially this technique useful in head injuries disorders in the brain or its part or spinal cord etc. then it is very much useful to detect in the growth of the embryo. You are sitting in a train, which is not moving. Then other expresses train, which comes near you, and pass by then you fell the intensity, frequency or pitch of the sound is increased to greater extent. But when it goes away the intensity of the sound goes on decreasing. Even through the sound remains the same before coming near to you but it increases When it passes by you . it is an apparent change in the frequency of the sound. Due to the motion of the body producing the sound this effect is called Doppler’s effect. Appearing the changes in the frequency of the sound by the relative motion of the body producing the sound and the absorver is called Doppler’s effect.

Uses:1. It is used to determine the speed of the submarine. 2. It is used to determine the speed of the moving vehicle. 3. Traffic authorities used this Doppler’s effect to determine the velocity of the moving vehicle wheather it has crossed the limit. 4. Doppler’s effect is very much used in light, also in the astrophysics, Doppler’s effect is used to study the speed of the satellite asteroids, comments and galaxies and it is used to study the ring system of Saturn.

In the spectrum the lines will shift to wards red colour this is called as red shifting that will help you to study the velocity of the galaxy or asteroid or the star.

Doppler’s effect :Doppler’s effect is the apparent change in frequency of wave motion due to the reltive motion between the source and the observer. 30

UDAYA English Medium High SCHOOL Std - X Applications of Doppler’s Effect 1) Doppler’s effect in sound can be used to determine the velocity of submarines. 2) Traffic control authorites use Doppler’s effect to detect vehicles crossing speed limit. Radio waves are used for the purpose. Radio waves are sent in the direction of the speeding vehicle and the reflected waves are received. The change in frequency of the wave is used to determine the speed of the vehicle. The instrument used for the purpose is called Radar gun. 3) Doppler Effect is used in tracking of artificial satellite. 4) Doppler Effect in light has many applications in astrophysics. It is used in the study of binary stars, Saturn rings, galaxies. Doppler Effect is also used to estimate speed of stars, galaxies and rotation of sun’s disc.

UNIT -11 RADIO –ACTIVITY A

=

z

+

N

(No.of

(No.of

Protons )

neutrons )

1. If the mass no. of uranium is 233 and no. of electrons are 92. Find the no. of other particles. Sound. Mass of uranium No. of electrons At no =no of protons = 92

= 92

At. Mass 233 233-92 141

= Z

=233 = no. of electrons

= 92

Therefore No. of protons No. of neutrons

+ N = 92 + N = N = 92 and no. of electrons =92 = 92 and no. of electrons =92 = 141

2. Calculate the no. of protons and neutrons. If the mass no. of radium is 266 and no. of electrons are 88. Solun. Mass of the radium

= 226 31

UDAYA English Medium High SCHOOL Std - X No. of electrons

= 88

At. No = no. of protons

= no. of electrons

At. No =

=

88

At. Mass

= Z

+

N

226

= 88

+

N

226 – 88

= N

138

= N

88

All the mater is made up of clements basically. These elements are in turn made up of similar kind of atoms. (an atom is the smallest particule of an element ) Atom of different elements are different in their characteristics. Structure of an Atom:It consists of a centrally located small nucleus, which is more massive. The entire mass of the atom is nearly concentrated in the nucleus. This nucleus consists of positively charged protons and uncharged neutrons. Negatively charged electrons moving in their specific orbits surround the nucleus. Electrons have negligible mass of about 1/1840 of mass of proton. In an atom the mass of the neutron is slightly greater then the mass of protons. In a neutral atom the number of protons is always equal to the number of electrons. Note:- in most of the elements the number of neutrons is greater then the number of protons. An element is symbolically denoted by =XA where ‘X’ is an element ‘ z ‘ is atomic no. atomic no. mass Protons which are also, equal to the no. of electrons. Mass no is the sum of no of protons and no of nucleons. i.e ‘A’ is equal to (Z + N). 3. what is the mass nbo. Of the Necleus that has 13 protons and 14 neutrons ? Souln. No of protons =

13

No of Neutrons Therefore, at Mass

At. Mass

=

14

=

Z

+

N

=

13

+

14

=

27 32

UDAYA English Medium High SCHOOL Std - X 4. what is atom no of Silion. If its mass no. is 30 and no. of neutrons is 16 ? Solun. At. Mass of Silicon

=

30

No of Neutrons Therefore, At Mass

=

30 30-16 Therefore At no of silicon

=

16

Z

+

N

=

Z

+

=

Z

=

14

16

Isotopes: They are the atoms of same elements having the same atomic no. but different mass no. Or The atoms of same elements having the same no of protons but different no of neutrons are called as Isotopes. Ex:

233 92U

, 92U235 , 92U238

H1 , H2 , H3 12 6C

, 6C14

Radioactivity:- It is a process of Spontaneous emission of highly powerful radiations due to the disintegration of an unstable nucleus. During this process some changed or unchanged particles may be liberated. Or The process of disintegration of an unstable nucleus with the emission of some changed or unchanged particulars is called Radioactivity.

Radioactivity Elements:-

The elements which can be disintegrate and emit powerful radiations are called Radioactivity Elements. Ex:- uranium, Radium, Thorium, Plutonium etc.

Radioactivity Elements:- The radiations produced by Radioactivity Elements are called Radioactivity rays. These rays may contain changed particles namely alpha and beta (‘a’, ‘B’) or unchanged particle namely gamma (Y). 222 Ex: (i) 88Ra226 + a particle 86Rn 238 234 4 (ii) 92U + 99Th 2He 33

UDAYA English Medium High SCHOOL Std - X Note: Radio – Activity was discovered by theory Bacquerel in 1895 Induced Radio – Activity : Radioactivity Elements:-it is a phenomenom in which a Radio – Activity substance is produced by bombarding a stable nucleus with high velocity alpha velocity alpha particles, neutrons, protons, etc. Ex: 1. 18AI27 + 2He4 ---- 15P30 + 0n1 Note: Elements upto calcium in the periodic table (except Helium, carbon and oxygen ) can produce Radio – Activity when bombarded with alpha particles. NOTE: all isotopcs are not Radio – Activity

Properties of Alpha Particles: 1. 2. 3. 4. 5.

Positively charged similar to 2He4 (have no electrons) Has a less penetrating power Has a less velocity. (1/10th velocity of light ) Have a very high ionizing capacity Affects the photographic plate

Properties of Beta Particles:

1. 2. 3. 4. 5.

Negatively charged particles nothing but an electron. (1eo, or ) Has a more penetrating power Has a more velocity (99% velocity of light ) Has a very less ionizing capacity. Affects the photographic plate.

Properties of Gamma Particles.

1. 2. 3. 4. 5.

Neutrally charged highly powerful electromagnetic radiations Has a very high penetrating power Velocity

= velocity of light

Has a least ionizing capacity Affect the photographic plate.

Note : 1. Whenever an alpha particle is emitted the atomic no. decreases by 2 and the mass number decreases by 4. 234 4 Eg: 92U236 + 90Th 2He 2. When a beta particle is given out the automic no. increases by one and there is no change in the mass no. during this process a neutron in the nucleus changes in a proton with the emission of an electron. Eg: 82P212



83Bi

212

+

4e

0

: Bi

-Bismuth.

34

UDAYA English Medium High SCHOOL Std - X 3. when a gamma particle is given out there is no change in the mass no or the atomic no. but the nucleus will have lost some energy in making a change form higher energy to a state of lower energy.

Transmutation:It is a phenomenon in which the parent nucleus of one elements is converted into the nucleus of a new elements Or The change of one element to another new element with the emission of some charged or uncharged particles is called transmutation. Eg:6C14 – 7N14 The original nucleus is called the parent nucleus and the nucleus of the new element is called daughter nucleus. Radioactive isotopes:- if the isotope of an element is radioactive the it is called as radio.Isotope ‘OR’ Raidonuclide. Eg:- 92U233 92U235 92U238 Iodine:-131,Cobalt:-60,Phosphorus:-32 Note :- Isotopes can be obtained artificially by suing neurons in a nuclear reactor,

Uses of Radio –Isotopes:1. Cobalts 60: Used to destroy cancer cells ,to check the machine parts,to preserve the food and weldings. 2. Iodine 131:- To detect brain tumor, detection and treatment of thyroid cancer. 3. Phosphorus 32:- Used in agriculture to study the absorption of Phosphorus by the plant to study the efficiency of different Phosphoric fertilizers,treatment of blood cancer, brain tumor etc. 4. Soduim 24:- to study the action of machines and blood circulation in the body 5. Carbon 14:- Is used to estimate the age of fossils and archaeological monuments Half –life period :- It is the time required for the disingration of one half of the original amount of the Radio- active substance to disintegrate or it is a time taken by a radio – active sample of the elements to get reduced to half its initial amount. Half - life of elements varies from micro – seconds to billions of years. Where ‘N’ is the amount of radioactive material and ‘T’ is the time to disintegration. Half – life of Radium is 1600 years. Half – life of polonium is 164 microseconds. Half – life of uranium is 4.5 X 10 years. Half – life of iron -59 is 44 days. 35

UDAYA English Medium High SCHOOL Std - X 1. Calculate the time required for 1 Mg of radium to decay into 125 Mg. if its Half – life is 1600 yrs Solun.

T=1600 yrs Therefore, time for 1.125 Mg of radium = 3T = 3 X 1600 = 4800 yrs. 2. The Half – life of polonium is 1.5 X 10.4 Sec. Initially if 2 Mg of substance is presented. What is the time required to disintegrate into 0.0625 Mg. 3. Solun. T = 1.5 X 10.4 Therefore, time required for 0.0625 Mg = 57 = 5 X 1.5 X 10.4 Sec. = 7.5 X 10.4 Sec.

UNIT -12 NUCLEAR ENERGY Whenever a new compound is formed a chemical reaction produces in which valence electrons are responsible for such chemical changes. During chemical reaction heat may be released or absorbed. But whenever changes take place within the nucleus heat is liberated. Electrons don’t take any part in such changes.

Nuclear Reaction A reaction in which changes take place within the nucleus of an atom is called nuclear reaction. Nuclear Energy (Atomic Energy) The energy released during a nuclear reaction is called nuclear energy.

Stability of Nucleus :The protons and neutrons are bound together and held within the nucleus mainly because of nuclear force. This force is a strong force of attraction exiting between protons, neutrons or protons and neutrons i. e. The force of attraction existing between the nucleons. 36

UDAYA English Medium High SCHOOL Std - X

The force is always attractive, independent of charges acting within a very short range of 10-15mts. . But within the nucleus there is also an electrostatic force which is repulsive existing between protons. But the nuclear force is stronger than the electrostatic force, due to this the nucleons stay within the nucleus. Thus the nucleus becomes more stable. In case of unstable nucleus the electrostatic force is greater than the nuclear force which are nearly balanced. In such cases the nucleus under goes changes very easily i. e. A very small energy is sufficient to break a nucleus. Binding Energy:The minimum energy required to separate the nucleons is called binding energy or the minimum energy required to overcome the nuclear force and thus break the nucleus is called binding energy. Note: Greater the nuclear force, greater the binding energy and greater the stable of the nucleus.

NUCLEAR ENERGY

Nuclear Fission

Nuclear Fussion

Nuclear fission : - This process was discovered by otto Hahn and Fritz Strassman is 1938. It is a process where a heavy nucleus breaks into two or more light nuclei with the emission of enormous energy.

By products of Nuclear fission :1. Two equal fragments called as nuclides two to three neutrons, hightly energetic particles or rays like alpha, Beta or Gamma and enormous energy. Eg.: Whe a highly fissible unstable uranium 235 nucleus is bombarded (hit) by slow moving neutrons, it breaks into Barium and Krypton along with production of three neutrons and high energy. 231 1 + on  56Ba141 + 36 Kr92 + 3on1 + energy 92U By just one such fission reaction 200 Mega electron volts of energy is produced. But Uranium 235 some times can also split into xenon and strontium or some times into Letheam and Bromine. 37

UDAYA English Medium High SCHOOL Std - X Chain Reaction It is a self-propagating continuous fission reaction which takes place just by the collision of a slow moving neutron or. It is a process in which the fission reaction on its own by the increase in the no. of neutrons and the release of high energy. Or it a self-propagation process in which the no. of neutrons go on multiplying rapidly till the whole material is disintegrated.

Cause for Nuclear Energy:When the mass of the initial nucleus is compared to the sun of the masses of the resultant nuclei it is seen that the initial mass is greater than the final mass. i. e. there is some mass difference called as mass defect. Denoted by m’. This difference in the mass if converted into energy called as nuclear energy, given by Einstein’s energy equation E = Mc 2, Where E is energy liberated, m is the mass defect and C is the speed of light.

Critical Size : If the size of fissionable materials is to o small the material does not absorb the incident neutrons and fission does not take place. Therefore some minimum size is required. The minimum size of the fissionable material required to start the fission reaction is called critical size.

Atom Bomb: Two fissionable materials each of sub critical size are fused together by high temperature to form a mass with a critical size. When a high velocity particle from the atmosphere strikes it fission reaction proceeds in an uncontrolled manner leading to a huge explosion. Nuclear Reactor: It is a device where energy is released in a controllers manned by nuclear fission reaction. Construction: The reactors core consists of the fuel which is enriched uranium of polonium 239 in the form of rods or pallets enclosed in a steel or Aluminum capsule, in between the fuel rods there is moderator made up of graphite heavy water or molybdenum which checks the speed of the neutrons in between the moderator there are control rods made of boron or cadmium which can be moved in and out and help in the absorption of the neutrons and in the shutting of the reactor. There is a coolant circulating in the reactor, which helps to move the heat produced during the 38

UDAYA English Medium High SCHOOL Std - X fission reaction. The coolant is ordinary water,heavy water,liquid sodium.liquid hydrocarbons or some salts solution. The reactor is safely placed inside the radiation shield made of lead surrounded by a thick concrete layer. This prevents the leakage of harmful radiations. This whole systems is connected to a heat exchanger in turn to a turbine and a generator.

Principle: The energy is liberated in a controlled manner during nuclear fission and converted into useful energy.

Working: The fission reaction is started by particle accelerators externally. As the reactions proceeds enormous heat is liberated. This heat generated is controlled by the moderator and controlled rods. This heat in turn heats the water and produces steam,which can run the turbines and produce electricity. Part Constituent 1 Fuel Enriched U or polonium 239 2 Moderator Graphite,heavy water or molybdenum 3 Control rods

4 Coolant

5 Radiation shield

Function Start fission Checks the speed of the neutrons. Boron or cadmium Can move in and out and help in the absorption of the netrons and in shutting of the reactor Ordinary water ,heavy h20 liquid sodium or Circular in the reactor hydrocarbon or some salts solution. help to move heat produced during fission reaction. Lead,surrounded by a thick concrete layer Prevents the leakage of harmful radiations.

Use of Nuclear Reactor 2. Generation of electricity (i.e Nuclear power plant) 3. Run Submarines and ships. 4.Manufacture of radio-active isotopes 5 Research purpose Disadvantages 1. Radio active wastes are harmful as they cause many diseases 2. It is different to discard (dispose) them 3. The fuel os costly and not easily available. 4. Setting if nuclear reactor is costly Thermonuclear Fusion Reaction 39

UDAYA English Medium High SCHOOL Std - X It is a process where two or more light nuclei combine to form a Heavy nucleus with the release enormous energy –talking please at high temperatures. It is called as thermonuclear fusion reaction because a very high Temperature of 105 to 107 K is required to start the reaction. Such a Reaction is seen in the stars. There high temperature is attained by the immense contraction of the star. Example ; Fusion reaction involves proton. Proton cycle or the carbon cycle. In both the cases 4 protons fuse to form helium with the release of energy, but in carbon, but in carbon cycle carbon is used as a catalyst. Products of nuclear fusion 1. heat and light energy 2. Alpha, Beat and Gamma rays 3. Electromagnetic radiations like infrared radiations, visible light, U. V. radiation, x – rays etc. Energy liberated per nucleon during fusion is greater than nuclear Fission. Hydrogen bomb It consists of a fissionable material at the centre, surrounded by Hydrogen. When a neutron strikes it is fission reaction starts and provides the necessary temperature to hydrogen. Hydrogen start combining rapidly giving out enormous energy in an uncontrolled manner leading to explosion. Disadvantages 1. Different to control the reaction 2. The radiation gives out may cause many diseases 3. It’s different to get free hydrogen 4. Different to obtain high temperature necessary to start the reaction 5. The containers which can store the raw material cannot withstand Such high temperature Different between fission and fusion reaction

1 2 3 4 5 6 7 8

Fission Breaking of a heavy nucleus Energy liberated is less Takes place at normal temperature The wastes are harmful Raw material is costly and not easily available Energy released can be controlled Chain reaction takes place Can be used for constructive and destructive purpose

Fussion 1 2 3 4 5

Large energy is liberated Very high temperature is required The wastes are harmless Raw material is cheap

6 7 8

Energy released cannot be controlled No Chain reaction For destructive purpose 40

UDAYA English Medium High SCHOOL Std - X UNIT-13 SOLAR ENERGY The energy obtained from the sun is called SOLAR ENEGRY. The sun emits energy in the from of radiations (rays). The earth receives only a small part of the solar energy because some part of it is reflected by the earth’s atmosphere. All the forms of energy and different activities on the earth are directly or indirectly are dependent on the solar energy ADVANTAGES:     

It is an inexhaustiblc source of energy. Free of cost. Easily available to all. Can be easily converted into other forms of energy. It is continues and non-diminishing. It is pollution free.

DISADVANTAGES:   

The harmful radiations can cause ill effects. Not available uniformly at all places and at all times. Solar devices are costly and hence unecomical. There is scattering of energy due to which there is wastage and thus difficult to get the required amounts.

Uses of Solar Energy:1. Direct Uses: Solar energy can be used directly in the following ways:  Light is directly used to see different things.  The heat energy of the sun can be used in devices like solar cookers,solar heaters, solar furnaces and solar cells. 2. Indirect use:  Used by the plants and converted into chemical energy i.e. food.  Formation of wind energy.  Tidal energy, wave energy is because of solar energy.  Heating up of the water in seas and oceans which can be used for different purposes. Solar Devices:41

UDAYA English Medium High SCHOOL Std - X These are the-devices, which use solar energy for different purposes. Eg: Solar cookers, solar furnaces, solar water heaters, solar cells etc. SOLAR COOKER: It is a device where solar energy is used to cook food. Construction:- It consists of a box made of wood or any heat resistant material. The inside wall of this box are painted black so as to absorb more heat. The box is covered with glass lid. So as to let in the radiation of the sun. The box is also fitted with moveable mirror. So as to reflect more heat on the box. Working:- The food to be cooked is placed in container painted black from outside. This container is placed inside the wooden box and covered with glass lid. This whole system is sunlight and the mirror is adjusted in such a way that more sunrays fall on the container. The rays of the sun mainly infra red radiations of longer wave length which are trapped inside by the glass plate. Thus the container gets heated up and the flood gets cooked. These cookers are not suitable for frying or baking the food because a low temperature of 100 to 140C can be attained. Therefore concentrated reflector type of cookers are preferred. Solar furnace:- It is a device where solar energy is used to melt the metals in a furnace.

Construction:- It consists of a parabolic reflecting mirror which may contain thousands of mirrors. So as to reflect more sun’s rays. At the focus of this mirror a furnace is placed. Working:- The furnace containing the metals to be melted is placed at the focus of reflecting mirror. When sufficient temperature of nearly 3000 to 35000C is attained the metal starts melting. Solar water heater:- It is a device where solar energy is used to heat the water.

Construction:- It consists of a tank situated at a higher level which contains cold water. This is connected to another tank at the lower level. The tank at the lower level is connected in the middle to an insulator box, which contains metallic pipes. These pipes are painted black so as to absorb more heat. These black pipes have water flowing through them. The insulator box is covered with a glass sheet.

42

UDAYA English Medium High SCHOOL Std - X Working:- The whole system is fixed in such a place that sufficient sunlight is incident on the box. As the pipes get heated the water becomes hot and gets collected on the upper layers of the tank at the top. The amount of hot water removed is replaced by cold water from the bottom inlet. SOLAR CELLS:- These are devices where solar energy is converted into electrical energy directly. The first solar cell was invented in 1954. Construction:- Wafers of semi conducting materials like silicon or gallium of area 4 sq cm is arranged in such a way that sufficient potential difference develops between two regions of the wafer when light falls on it. Working:-when light falls on the semi conductor a potential difference is developed between two ends of a cell connected to a battery. Atoms start releasing electrons thus producing electricity. This develops a potential difference of about 0.4 to 0.5 V supplying a current of 60 milli amperes. High power can be developed by arranging a number of cells in series on large flat sheets constituting a solar panel. Uses:       

To charge the batteries in spacecrafts and satellites. To provide electricity in remote or isolated places. In T.V and radio broadcasting stations. In solar calculators and watches. In lighthouses and off shore drilling areas. In traffic signals and off shore drilling areas. In traffic signals and react arch centres. Domestic lighting.

Solar cells are not widely used because they are expensive.

43

UDAYA English Medium High SCHOOL Std - X Unit -14 ENERGY CRISIS Energy is defined as the capacity to do work. This energy is mainly required to carryout the different activities. It can be obtained from different sources like wind, burning of fuel, sun. Due continuous use some of the energy source may become extinct. Depending on the available the energy sources can be classified into renewable source and non – renewable source. Renewable Source:The source of energy, which do not decrease even after continuous use, are called renewable source i.e., they don’t get exhausted because they are always recycled in the nature. Ex: Solar Energy , Water Energy etc.

Non –Renewable Sources:The source get depleted or become extinct after a prolonged use. Ex: Fossil fuels, Minerals Energy Crisis It is a condition resulting due to the scarcity of energy sources or a condition, which has arisen due to the imbalance between the supply and demand for energy. Causes:1. Population incfease which corresponds to increase in energy Exploitation and over use of non –renewable sources. 2. Consumption 3. Increase use of vehicles as led to the over use of the fossil fuels. 4. Wastage or improper use of energy 5. Improper maintenance of machines. 6. Improper storage methods. 7. More demand for luxurious items. Wastage water 1. Leaking water taps, dripping taps, leaking wolves in water pipes. 2. Damage of water pipes during transportation. 3. Polluting the water bodies 4. Improper storage of water 5. Over use of underground water. 6. Keeping the water taps are on when they are not in use. 7. Using drinking water for other purpose 8. Cutting down of trees, which decrease the rainfall. 9. Over use of water in agricultural areation

44

UDAYA English Medium High SCHOOL Std - X Wastage of Electricity:1. Using luxurious items, which consume more electricity. 2. Loss during transportation of electricity. 3. Keeping the electrical devices on when they are not in use 4. Using inefficient electric devices Ex; Incandescent light 5. Improper construction of building which lacks sufficient ventilation and light resulting the use of fans and lights. 6. Illegal use of electricity 7. Improper use of electricity in public places. Wastage of Fossil Fuels:1. Overuse of firewood, charcoal etc. 2. Improper maintenance of vehicles, which consumes more fuel. 3. Using the bad quality of fuel and improper design of vehicle. 4. Bad quality of roads which consume more fuel. 5. More amounts of fossil fuels are used by the increasing population of vehicles. Measure to Prevent energy crisis:1. Maintain good roads 2. Use efficient fuels 3. Machines should be lubricated and properly designed and maintained. 4. Use renewable source. 5. Alternative source like biogas, nucleus energy and solar energy should be used. 6. Florescent tubes should be used instead of incandescent bulb. 7. An arrangement to control electric power in public places. 8. Reduce the loss of electricity during transmission by proper wiring 9. Use efficient cooking devices like pressure cookers. 10. Proper ventilation and lighting in construction of buildings 11. Attend the leakages of water regularly 12. Government has to provide other alternate arrangement for water required for other activities. Thus minimizing wastage of drinking water. 13. Store the flowing water or flood water by constructing dams and reservoirs. 14. Plant more trees so as to get more rainfall. 15. People should be educated about the importance of energy and methods to save energy. 16. Waste materials should be recycled. 17. Population explosion should be controlled.

45

UDAYA English Medium High SCHOOL Std - X Unit -5 METALS Earth is the storehouse of large quantity of resource. The crust of the earth consists ores and minerals of different metals. The metal available in large quantity is alumnium [A1] ,next to aluminium the metal found in abundance is iron [Fe] The list of order of abundance of metals.Available in the earth crust is iron [Fe] The list of order of abundance of metals.Available in the earth crust is 1] Aluminium [A1] 7% 3] Calcium 2.5% 5] Magnesium 2%

2] Iron [Fe] 4% 4] Potassium 2.5% 6] Titanium 0.6%

PHYSICAL PROPERTIES OF METALS 1] All metals exists only in soild state except mercury 2] Metals are lustrous [means they have shining surface i.e. thier surface can be polished] 3] Metals are good conductors of heat and electricity 4] They have high bioling point and melting point. 5] They are malieable and ductile [they can be made in to thin sheets and wires] 6] They are Electro positive elements. 7] Metals are hard and have high density. 8] Metals are sonorous 9] They are thermo ionic in nature 10] They have high specific gravity.

CHEMICAL PROPERTIES OF METALS 1) With Oxygen : When metals are heated strongly in oxygen they form their respective oxides. Ex- when magnesium is heated strongly it burn in oxygen with brilliant light producing 2Mg+O2 ->2MgO

Similarly 4Fe+O2 Heat 2Fe 2O3 2Pb+O2 Heat 2Pbo 4AI+O2 Heat 2AI2 O3 2) With Chlorine: Metals reacts with chlorine forming thier respective chlorides. Ex :When heated aluminium powder is sprinkled into a jar containing chlorine, aluminium reacts with chlorine forming flashes of light giring aluminium chloride. 2A1+3Cl2 ----- 2A1Cl3 46

UDAYA English Medium High SCHOOL Std - X (Heated powder A1) Ex : when a piece of sodium is dropped into a jar containing chlorine, it forms sodium chlorine 2Na+C12 ---- 2NaC1 3) With Sulphur: Metals react with sulphur forming thier respective sulphities. Ex: When powdered iron and sulper in proper proportion are heated strongly, a black mass of ferrous sulphite is formed. Fe + S ---- FeS Similarly (i) Pb + S ---- PbS (ii) Cu + S ---- CuS 4) With Water: Many of the metals will not react with water. Aluminium reacts with steam, where as the active metal sodium vigorously with water moving randomly making a hissing noise forming sodium readily reacts with water. When a piece of sodium is dropped into water forming sodium hydroxide and liberates hydrogen gas. Ex: 2Na+2H2O ---- 2 NaOH + H2 5) With Dilute acids:- Metals react with dilute acids and liberate hydrogen gas. Ex- 1) Zinc reacts with dilute hydrochloric acids and liberates hydrogen. Zn+2HC1 ------ ZnCl2+H2 2) Iron reacts with dilute sulphoric acid liberating hydrogen. 3) Copper reacts with dilute nitric acid liberating hydrogen. Cu+2HNO3 ---- Cu (NO3)2+ H2 6) With concentrated acid:- Metals like calcium and magnesium reacts with concentrated sulphuric acid forming their respective sulphates liberating sulphurdioxide Ca+2H2 SO4 ---CaSO4+SO2 + 2H2O Mg+2H2SO4 --- MgSO4+SO2 + 2H2O Displacement reactions some metals displace other metal from their salt solution. Such reactions are called displacement reaction. Ex- Iron & zinc displaces copper from copper sulphate solution Fe+CuSO4 ----- FeSO4 + Cu Zn + CuSO4 --- ZnSO4 + Cu Occurrence of metals Metals occur in 2 forms 1) Native form (free state) 2) Compound form (combined state) 47

UDAYA English Medium High SCHOOL Std - X Metals which are not reactive at ordinary temperature occur in Native for or Free State. Ex-Gold, silver, platinum etc. Metals which are active at ordinary temperature occurs in compoud form or ombined state. Ex-Iron, copper, Aluminium, Son Nickel, potassium Ores etc. Minerals and ores:- A mineral by naturally occurring substation in which metals is present along with impor A mineral by which metals can be extrac profitabaly and economically is called ore. All ores are minerals, but all minerals are not ore.

Ores of different metals and their Sl. no 1 2 3 4 5 6 7 8 9

Metals

Name of the ore

Composition

Iron Copper Aluminium Manganees Magnesium Chromium Zinc Lead Sodium

Heamatite magnetite Chalcopyrite Bauxite Pyrolusite Magnesite Chromite Zincblande Galena Rock Salt

Fe 2 03 fe3 o4 CuFes2 Al2O3 2H2O MnO2 MgCO3 Cr2O3FeO- Cr2FeO4 ZnS Pb3 NaCl

Metallurgy:- The technology of extracting metals from the respective ores and refining them is called metallurgy. The 3 steps of metallurgy are. 1) The concentration of ore:- The process of eliminating all the gangue materials like sand, stones, lighter particles, insoluble particles, insoluble particles to increase the percentage of ore is called concentration of ore. The different methods of concentration of ore are. a) Hydraulic washing b) Froath floation c) Magnetic separation d) Chemical separation 2) Reduction of the ore The process of removing oxygen from ore to obtain the metal is called reduction of the ore This can be done by (a) Reduction by coke (b) Fe2 O3 + 3CO --- 2Fe + 3CO2 (c) Reduction by aluminium. 3) Refining of the metals Purification of the metal is called refining of metals. The best method of refining metals is Electrolytic refining. Extraction of Iron:48

UDAYA English Medium High SCHOOL Std - X Iron is extracted from its ore Hematite (Fe2O3). The ore is concentrated by Hydraulic wash. In this method a gush of water is passed through powdered iron ore taken in a chamber, then all the gangue particles are carried away by the water and only heavier particles of the ore and silicon dioxide remains in the chamber. This iron is extracted from the concentrated ore in a blast furnace. In the blast furnace SiO 2 is removed by making it to react with calcium carbonate (CaCO3). Ferric oxide is reduced to iron by using coke as reducing agent. A blast furnace is a cone shaped tall steel vessel having a lining of refactory bricks which can withstand very high temperature. The change which is a mixture of concentrated iron ore, calcium carbonate and coke is brought to the top of the furnace and produce into the charge container (Fe2 O3 + CaCO3 + coke). This change is poured into the furnace from the top. Simultaneously a blast of hot air is passed from the bottom of the furnace.

This heats up the mixture and the following reaction takes place in the blast furnace. 1. Calcium carbonate decomposes to give calcium oxide and carbon dioxide. CaCO3 --- CaO + CO2 2. Silicon dioxide reacts with calcium oxide and forms calcium silicate which is a slag of impurities. SiO2 + CaO ---CaSiO3 (slag of impurities) 3. Coke burns in oxygen and forms carbon monoxide, this carbon monoxide reduces ferric oxide into iron. C2 + O2 -- 2CO Fe2O3 + 3CO --- 2Fe + 3CO2 Molten iron collects at the bottom of the furnace and the slag of impurities floats on molten iron. The slag is removed and the molten iron is tapped out. The slag of impurities prevents the oxidation of the molten iron into ferric oxide; because it floats on the molten iron. Iron extracted in the blast furnace is called pig iron. This pig iron again consist of sulphur, phosphorous , calcium, magnesium as impurities. These impurities are removed either in bassemer converter or open hearth furnace to manufacture steel. Note : 1) In this process calcium carbonate (lime stone),remove silicon dioxide to form slag of impurities of calcium silicate. 2) Coke is used as a reducing agent. 3) Steel is manufactured from pig iron either by Bessemer converter or open hearth process. Extraction of copper : 49

UDAYA English Medium High SCHOOL Std - X Copper is extracted from its sulphide ore called chalcoyrites. Its composition is CuFeS 2 Copper ore is concentrated by froth flotation method. In this method a mixture of water and pine oil is taken in a tank. finely powdered ore of copper is added to this mixture. The mixture is agitated by blowing air. The finest ore particles stick to the pine oil bubble and forms a froth over the tank. the gangue particles collect at the bottom of the tank . The froth is skimmed off and is used to extract copper. Thus the ore of copper is extracted. The froth containing CuFeS2 is roasted in air, this forms cuprous sulphide, ferrous oxide and liberates SO2 . CuFeS2 + 4O2 roasting Cu2 S+2FeO + 3SO2 The mixture of Cu2s and 2FeO are heated with SiO2. Ferrous oxide changes into ferrous silicate (FeSiO3) slag. FeO + SiO2 heat FeSiO3 (slag) This slag is tapped out of the furnace . Cu2S is again roasted in a current of air and practically converted into cuprous oxide (Cu2O). 2Cu2S + 3O2 -------2Cu2O + SO2 The current of air is stopped , then Cu2O reacts with Cu2S . 2Cu2O + Cu2S --- 6Cu + SO2 The reaction between the cuprous oxide and cuprous sulphide to get copper is called bessimarization thus copper is extracted . In this process sulphur dioxide is liberated through the solidifying copper therefore blisters are formed over the copper extracted. Thus the copper is called the blister copper. This blister copper is impure copper, therefore it is purified or refined by the electrolytic refining method. In this method a series of impure copper plates are taken and they are connected to one another and made anode by connecting them to the positive terminal of the battery. A series of pure copper plates are taken and they are connected to a negative terminal of the battery to make cathode. As the current flows through the electrodes, the impure copper blocks and collects on the cathode .As the copper plate thickness increases pure copper is collected on cathode. These two series of plates are immersed in an electronic tank consisting of copper sulphate solution. As the current flows through the electrodes, copper ions are liberated from the impure copper blocks and collect on the cathods which are thin and pure copper plates. As the pure copper plates thickness increases sufficiently it is understood that pure copper has collected on cathode. Pure copper plates are taken out and washed with water thus the refining of copper is made and copper is purified. Alloys The homogenous mixture of two or more metals or a metal with one another non metal is called an alloy. The property of n alloy is different from the properties of its constituent elements. Alloy of Iron 50

UDAYA English Medium High SCHOOL Std - X The two main alloys of Iron are 1) Steel 2) Stainless steel

1) Steel It is an alloy of Iron with 0.5% to of 1.5 of carbon It constituents are Iron and carbon. It is extremely hard and strong Uses: a) Used in making nails, screws. Grinders. Railway vehicles. Ships and in construction of houses and of buildings. There are two types of steel 1) Mild steel 2) Hard steel 2) Stainless steel Its an alloy of Iron having carbon 0.47% 87% and chromium – 18% Its properties are 1) It won’t rust 2) It is unaffected by acids 3) It always maintains its lusterous surface 4) It is unaffected by chemicals present in food. 5) It is non attracted by the magnet. 6) It resist corrosion. Uses 1) It is used in making surgical instruments, knives, tools, scissors, blades etc. 2) Nickel steel Components : Iron and Nickel Uses a) Used in drilling instruments b) Used as utensils 3) Alnico Components Iron, Aluminium, Nickel, and cobalt Uses a) used in making permanent magnets 4) Invar steel Components : Iron Nickel, carbon Uses a) used in making cloth pendulum and measuring tapes 5) Nichrome Components:- Iron, Nickel, chromium Uses a) used in heating coin in electric stores Alloy of copper: The main alloy of copper is Brass. It is malleable and it has copper -80% and zinc 20% Sl No 1

Alloys

Constituents

Properties

Uses

Brass

Cu-90% Zn – 20%

It is Malleable, a) used in making electrical parts strong, golden tubes, nuts, bolts, utensils and colour fancy lamps. 51

UDAYA English Medium High SCHOOL Std - X 2

Branze

Cu-90% Sn-10%

3

German Silver

4

Gun Metal

Cu – 60% Zn – 20% Ni – 20% Cu – Sn (tin) Zn

Very tough, highly resistant to corrosion It has no silver its surface is silver

a) it is used in making statues, medals, bells, coins, cooking utensils a) used as electroplating resistance wires a) it is used in making the baralles of the gun, aears casting.

Notes

UNIT -16 NON -METALS The modern periodic table consists of more than 110 elements among these elements 22 elements are non metals. Among these 22 elements 1) 11 nonmetals are in gaseous state Ex – Nitrogen, Hydrogen, oxygen, Flourine, chlorine and all other noble gases or insert gases. 2) 1 non metal is in the liquid state Ex- Bromins 3) 10 non metals are in solid state Ex- Phosphorous, carbon, Silicon, Sulphur, Boron germanium etc. AVAILABILITY OF NONMETALS : In the atmosphere we get nitrogen, oxygen, hydrogen. The oceans consists of oxygen, hydrogen, cholorine and flourine. In the earth crust a) the nonmetal present in gaseous state and is available abundantly is oxygen a) The nonmetal is the solid state available in large quantity is silicon. PROPERTIES OF NON METALS : 1) Nonmetals exists in solid liquid and gaseous state. 2) The nonmetals are non lustrous (means they do not have shiny surface except graphite and iodine) 3) Non metals are had conductors of heat and electricity except graphite. 4) They have low boiling point and melting point. 5) They are non-malleable and non-ductile. 6) They are soft and light 7) They are non sonorous [means when dropped they do not produce sound] 8) They have low density. 52

UDAYA English Medium High SCHOOL Std - X CHEMICAL PROPERTIES OF NON METALS 1) They are electronegative elements. They accept electrons and become negative ions. 2) They combines with oxygen to from acidic oxides. 3) They do not displays hydrogen from acids. 4) They combine with chlorine to form covalent chlorides. 5) With oxygen nonmetal forms oxides (a) C+O2 --- CO2 (c) S+O2 --- SO2

(b) 2H2 +O2 ---(d) P4 + 5O2 ---

2H2O P2O5

1) With hydrogen non –metals forms respective hydrites (a) C+ 2H2 --- CH4 (b) 2C1 + H2 --- 2HC1 (c) N2 +3H2 --- 2NH3 (d) H2 +S --- H2S 2) with chlorine Non metal forms chlorides a) 2P + C12 --- 2PC13 b) C+2C12 --- CC14 c) P4 + 10C1 2 --- 4PC15

Silicon :- Silicon is a non metal 1) Symbol Si 2) Mass no 28

2) Atomic No. 14 4) Electronic configuration 152 252 2P6 352 3P2

It forms only single bonds with other elements. It has 4 electrons in the outermost shell. Position in the periodic table silicon has 4 electrons in the outermost shell. It is placed in the IV a group as the second elements below carbon. The other element in these groups are germanium. Tin, lead. Occurrence of silicon does not occur in free state in nature. It is the second abundant element. In the earth crust. It always occurs in the from of silicon dioxide and silicates. The simplest compound of silicon and oxygen is called silica (sio2 ) which is common sand The most common form of silicon is silicon di oxide. The 4 important varieties are formed in which silicon exists are (a) Sand (b) Flint (c) Quartz (d) Opal Silicates occur naturally in the igneous rocks and clay. Mica is a transparent mineral of silicate sheets. Another minerals of silicon is feldspar (kaisio 38) (composition of feldspar)

Preparation of silicon st

1 Method : Silicon is prepared by heating finely powered silicon dioxide with carbon which is in the form of coke in an electric arc furnace. 53

UDAYA English Medium High SCHOOL Std - X SiO + 2C ------ Si + 2C 2nd Method: Finelly powered Quartz is strongly heated with magnesium along with calcinated Magnesia in a fire clay crucible. Silicon is formed alond with magnesium oxide is dissolved in dilute hydrochloric acid and silicon dioxide is separated. SiO2 + 2Mg ----------Si + 2MgO Physical properties of silicon 1) It is gray in color hard and shiny solid 2) It has melting point of 14100c 3) It is insoluble in water and does not react with it. 4) It has low conductivity – It is semi conductor 5) It is a hard crystalline solid substance having atomic arrangement similar to diamond. Chemical properties of silicon 1) With oxygen :- when silicon is heated strongly in oxygen it forms silicon dioxide. Si + O2 ---SiO2 2) With chlorine :- it reacts with chorine at temp. 4500c forming silicon tetra chloride. Si + 2Cl2 =---- SiCl4 3) With steam :- silicon reacts with steam forming silicon dioxide liberating hydrogen Si + 2H2O ---- SiO2 + 2H2 4) With hydrochloric Acid: silicon reacts with hydrochloric Acid forming silicon tetra Chloride liberating hydrogen. Si + 4HC1 ---- SiC14 + 2H2 5) With Sodium :- Silicon reacts with sodium Hydroxide forming sodium silicate liberating hydrogen. Si + 2NaoH + H2O ------ Na2Sio3 + 2H2 6) With Metal:- when magnesium and silicon are heated strongly in an Electric aric Furnace magnesium silicate is formed. 2Mg + Si --- Mg2Si

(Magnesium Silicate)

Uses of silicon and compounds of silicon 1. Application of silicon in Electronic Industry :The important application of silicon is in the production of integrated chips (Ics). This has revolutionized the electronic industry. Silicon is a semi conductor. It has ability to conduct lower then the metal and 54

UDAYA English Medium High SCHOOL Std - X higher then the non –metals. There fore in electronic industry it is used as semi conductor devices like transistors. It is used in making micro- Processor – silicon chips. A micro processor is made up of thousands of transistors arranged on a single ship of silicon. Thus silicon plays a vital role in electronic industry. 2. Silicon Carbide (Sic) It is also called Carbon random. It is prepared by heating silicon di oxide with coke in an electric are furnace. Sio3 + 3c ------- Sic+2co It is very hard substance, therefore it is used in making cutting and grinding tools. 3. Silicons: Organic polymers prepared by using silicon are called silicones. They are used in making water proof clothes, polishers, insulating materials, rubbers, lubricants, and greeces. 4. Silicon dioxide It is used in manufacture of cement and glass. 5. Alloy of metals with silicon 1. Silicon is used in the preparation of important alloys of iron, alluminium, copper, manganese. The major use of silicon in an alloy of iron is called Ferro silicon. It is used in the making of silicon steel. 6. Sodium silicate It is called water glass, its solution is used to preserve eggs. It is also used in making chemical garden in the laboratory.

UNIT -17 HYDROCARBONS The branch of chemistry, which deals with carbon compounds, is called organic chemistry. The compounds of carbon are used in the manufacturing of synthetic fibres and razines, dyes and drugs, plastics, soaps and detergents, in secticides and pesticides. Properties of carbon 1) Carbon shows tetravalency Valency of carben is 4. The atomic number of carbon is 6 its electronic configuration is 2 1s 2s2 2p2

According to the configuration carbon should show valency 2. But during reaction one of the electron is 2S2 orbital shifts to 2P2 orbital. Thus its configuration becomes 1s 2 2s1 2p3

It has 4 unpaired electrons and shows tetravalency. 2) Catenation 55

UDAYA English Medium High SCHOOL Std - X The property of carbon atom to combine with another carbonation to form straight chain is called catenation. EX:-

| | | | | | ―C―C―C―C―C―C― |

Straight chain

| ― C― | ―C―C―C―C―C―C― | C | ― C― |

Branched structure

CH

CH2 CH2

CH2

CH2

CH2

CH

CH

CH

CH

CH2

CH2

CH2

CH

Ex:- Carbon combines with other carbon atom forming single, double and triple bond. Classification of organic compounds Organic compounds are classified into 4 main groups 1) Aliphatic compounds They consists of open chain compounds. 2) Alicyclic compounds They have ring structured compounds. 3) Aromatic compounds They have atleast one benzene ring. 4) Hetrocylic compounds Along with benzene ring they have one functional group. Definition: Organic compounds having only hydrogen and carbon are called hydrocarbons, the simplest hydrocarbon is methane, 56

UDAYA English Medium High SCHOOL Std - X The representation of arrangement of carbon atoms along with bond is called structural formula Ex:- 1) methane –CH4 The main source of hydrocarbon is petrolatom. It consists of hydrocarbon in which carbonation range from C5 to C35

Classification of Hydrocarbons Hydrocarbons Openchain

closed chain

Hydrocarbons

Hydrocarb

Saturated unsaturated alicylic aromatic Hydrocarbons hydrocarbons hydrocarbon hydrocarbon Ex- 1) Cyclo Propane 2) Cyclo Pentone

1) Benzene Tolune 3) Napthalene

ALKANE ALKENES ALKYNES Saturated and unsaturated hydrocarbons Saturated hydrocarbons Hydrocarbons which contains only single bond between the carbon atoms and all the valences of carbon are completely satisfied then they are saturated hydrocarbons. Ex:- Methane – CH4

Ethane –C2H6

Propane –C3H8

Unasaturated hydrocarbons Hydrocarbons which contains at least one double bone oor triple bond between the carbon atoms and valencies of carbon atom are not completely satisfied then they are unasaturated hydrocarbons. Ex:- Ethane – C2H4

Ethyne – C2H4

Saturated hydrocarbons -ALKANES

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UDAYA English Medium High SCHOOL Std - X A cyclic hydrocarbons These are called alkanes They are saturated hydrocarbons They have only single bond between the carbon atoms. The name of the compound ends in “ane” A cyclic hydrocarbons are called paraffins. This means they show little affinity to form compounds with other active elements. 6) Therefore most reactive element sodium is preserved in kerosene, because kerosene is saturated hydrocarbon. 7) They have a general molecular formula. ALKANES- CnH2n+2 1) 2) 3) 4) 5)

Where n= 1,2,3,4,5,…………..n The molecular formula of these compounds and their structure are as follows ExEthane - CH4 Propane C3H8 Butane - C4H10 Pentane C5H12 ALKYNES 1) These are unsaturated hydrocarbons 2) They have at least one triple bond between the carbon atoms. 3) The name of the compounds ends in “yne” 4) These are called Olefins because they produce oily substances. 5) Their general molecular formula of these compounds ALKUNIES – CnH2n Where n= 1,2,3,4,5,…………………….. 6) The molecular formula of these compounds and their structure are as follows: 1) Ethyne – C2H4 (Acetylene) 3) Propyne C3H6 2) Butyne _ C4H8 4) Pentyne _ C5H10 Cyclic Hydrocarbon Hydrocarbons having cyclic structure are called cyclic Hydrocarbons. They are also called carbon cyclic Hydrocarbons. These Hydrocarbons are saturated cyclic; Hydrocarbons. There fore they are called Alicyclic compounds. Ex1. 2. 3. 4.

Cyclo propane = C3H6 Cyclo butane - C4H8 Cyclo pentane - C5H10 Cyclo Hexane – C6H12

Acyclic Hydrocarbons are saturated by drocarbon. Their general molecular formula is Cyclo hexane – CnH2n Where n= 3,4,5,……………………. 58

UDAYA English Medium High SCHOOL Std - X Aromatic ; Hydro carbons Aroma –m(means) odour These are unsaturated Hydrocarbons having ring structure. These compounds have a characteristic odour (smell) The simplest atomatic compound is benzene – C6H6 Its structural formula is The ring structural for benzene was given by Kekule Some other examples for aromatic compounds 1)

Toluene

2) Phenol 3) Anilin (Benzyl amine) 4) Nepthalene

Benzene is used for dry cleaning purpose as a very good solvent 7 in preparing dyes, med polymers and perfumes. Toluene is used also as a solvent and in the manufacturing of TNT (TriNitoTolune) Isomerism: (Iso-same, merism – arrangement) Organic compounds having same molecular formula but different structural formula are called Isomers. This phenomenon is called Isomerism. Ex- Butane and pentane shows isomerism. Isomers of Butane 1) Butane – C4H10 2) Pentane – C5H12

Hydrocarbon fuels The main hydrocarbon fuels are :- petrol, diesel, kerosene, liquefied petroleum gas, biogas and natural gas.

Petroleum It is a mixture of several hydrocarbon having carbon atom C5C10. It is a dark brown liquid. Petroleum is found in the deep of the earth under the rock beds. By means of drilling holes sinking pipes and pumping petroleum is brought to the surface of the earth. This process i\s called oil rigging. Petroleum obtained is called mineral oil or crude oil. It is a mixture of serval hydrocarbons having different boiling points. It is subjected to the process of separating various components of

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UDAYA English Medium High SCHOOL Std - X the petroleum from one another is known as refining of petroleum. This refining is done by a process called fractional distillation. The process of separating two or more mixable liquids having different boiling points by heating the mixture and condensing the vapour is called fractional distillation. The sand and water present in crude oil are separated mechanically and sodium hydroxide to remove acid and basic impurities. The crude oil is passed through heated pipes and allowed to go inside a fractional tower vapour raises upwards and at different heights, different fraction of petroleum condenses. 1) First the components having high boiling point will condense at lower fractionating columns and the fractions ( products having lower boiling point condenses higher fractionating columns. The uncondensed gas comes out from the top. At the bottom of the tower residual oil collects. The four main products of petroleum which condenses in the fractionating tower are :1) Petrol 2) Kerosene 3) Diesel oil 4) Fuel oil. When the residual oil is again subjected to vacuum, paraffin wax and bitumen. Cracking The process of breaking up of large molecules of hydrocarbons which are less volatile into smaller molecule of hydrocarbons having higher volatility is called cracking of petroleum. It is carried out at a temp. of 650 C using finely divided nickel as catalyst. The lower molecular masses of hydrocarbons are used as suitable fuels for automobiles. Ex- when Octane is heated at 650 C in the absence of oxygen it forms Ethene, hexane C8H18 ---C6H14 + C2H4 When normal hexadecane is subjected to cracking, it forms n octane and Octene. C16H34 --- C8H18 + C8H16 The unasatuarated hydrocarbons produced during cracking or used as raw materials for the manufacturing of polymers and petrochemicals.

Petro chemicals Chemicals which are obtained from petroleum or natural gas are called petrochemicals. Some of them are Butane, propane, pentane, butane, pentane etc. these petrochemicals as further used as raw materials. To manufacture dyes, drugs, polymers, fibres, pesticides, Fungicides etc. there are more then 50,000 petrochemicals are used in various fiels.

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UDAYA English Medium High SCHOOL Std - X Natural gas. It is a byproduct of petroleum well. Natural gas is the mixture of 80% methane, 13% ethane and other hydrocarbons in small quantity.

Properties:1.It is a clean and efficient fuel. 2.It will not produce smoke during combustion . 3.It has calorific value 50Kg/gm

Uses 1.It is used in tire industry 2.It is used widely as a domestic fuel. 3.It is used in automobiles as (Ng- compressed Natural Gas 4.It is used as a source of heat for industrial boilers. 5.It is used in the manufacturing of formal device methanol 7 carbon black.

L.P.G(Liquid Petroleum Gas) It is a mixture of several hydrocarbons . The main components of L.P.G is Butane . Since butane can be liquified at ordinary temperature, the liquid butane is filled in steel containers and used as a very good domestic fuel. L.P.G has a calorific value 55kg/gms or 2900kg/mole The leakage of L.P.G can be detected with its characteristic smell. This smell is due to Ethyl Mercaptan added to the gas.

Emission test:The automobile releases a large amount of carbon monoxide into the atmosphere. About 70 to 80 % of CO get released by the automobile exhaust according to the government pollution act , each type of vehicle is prescribed to emit a certain amount of carbon monoxide.. Ex:- Emission of CO of cars is allowed up to 3%. The test conducted to determine the % of carbon monoxide released by an automobile is called emission test. The percentage of carbon monoxide released by the vehicle is determined by an instrument called gas analyser.

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UDAYA English Medium High SCHOOL Std - X UNIT -4 SYNTHETIC MATERIALS Materials not available in nature but produced by using naturally available raw materials are called Synthetic material. Polymers Polymerisation: The process of obtaining a single large molecule by joining a number of smaller molecule is called polymerization. The large molecule is called polymer and the smaller molecules are called monomers. Ex - When Ethene gas is heated to a temperature of 200C under a pressure of 2000 at atmosephere it polymerizes to form a solid polymer called polythene. Types of polymerization 1.Addition polymerization :- The process by which a polymer is formed by simple addition monomers without the liberation of smaller molecules is called addition polymerization. 2. 3. Condensation polymerization:- The process by which a polymer is formed by condensation reaction between the monomers with the liberation of smaller molecules such as water , alcohol , is called condensation polymerization. 4. Polymer:-Polymer is a joint molecule of higher molecular wieght which is formed by the repeated union of a large number of simple molecules called monomers.

A polymer is a macro molecule monomers are the plastic units of polymers. They are building blocks of polymers monomers forms a polymer through covalent linkage.

SOME MONOMERS THEIR POLYMERS, USES and TRADE NAMES SL No 1

MONOMERS

POLYMERS

TRADE NAMES

USES

CH2=CH2 Ethene

(-CH-CH-)n Polythene

Polythene

2

CH2=CH-C1 vinyl chloride

PVC

3

CF2=CHCH=CH2 Tetra fluro ethane

(-CH-CH-)n C1 poly vinyl chloride (-CF2-CF2-)n polytetrafluroethene

Used for making toys, containers, pipes, bags etc Used for preparing floor tiles, toys, water pipes, shoe soles etc. Nonstick coating on kitchen utensils

Tefflon

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UDAYA English Medium High SCHOOL Std - X 4

5

6

CH2=CHCH=CH2 Butadiene styrene

(-CH2-CH=CH-CH2-)n Poly butadiene

Sytheticrubber

Used as alternate to natural rubber

Poly styrene

Thermocol

Eurathene floride

Poly Eurathene floride

PUF

Used as packing material and in making models Inner coating of refrigerator

Domestic and industrial uses of some polymers 1. Polythene:a) It is used in making pips, bags, buckets, thumblers etc. b) It is used in making film tapes and sheets. c) It is used as an insulating material like cables. d) It is used in making comman polythene bags.

2. Terylene:a) It is used in making fibres. b) It is used in making magnetic tapes. c) It is used in making water hoses pipes in fire fighting operation. d) It is used in making terrycot and terrywool. e) It is used in making sail boats. 3. Nylon:a) It is used in making fabrics. b) It is used in making brushes and sports equipments. c) It is used as an engineering material to make bearings gears and rolers. 4. Rayon a) Used in texitile industries for making fabrics like sarees. b) Used in tire industries for making tire cords. c) Used in manufacturing of carpets. d) Used in medical field for making bandages and surgical dressings. 5. Neoprene a) used in making electrical wire and tables. b) used in making wires in motor engine. c) used in making conveyer belts for coal mines. d) used in making flexible pipe for petrol delivery transporting oil as hoses pipe in industry.

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UDAYA English Medium High SCHOOL Std - X 6. Thermocol a) It is used as best packing materials. b) Used as material to prepare models. 7. Tefflon a) It is used as a coating for non stick kitchen utensils. 8. PVC (Poly Venyl Chloride ) a) Used in making water pipes. b) Used to prepare shoe soles. c) Used in preparing toys.

PLASTICS Plastic is a synthetic material manufactured by the polymerization of organic substances, which can be moulded into desired shape when it is hot.

Types of Plastics 1) Thermo plastics : plastics which loose their shape of heating are called thermo plastics. Ex- Polyvinyl chloride. Polyesters. 2) Thermosetting plastics : plastics which set on heating and become irreversible hard on cooling, are known as Thermosetting plastics. Ex- Bakelite, silicones, epoxy – resins. Uses of plastics: a) Polymers popularly termed as plastics, are substitutes to many structured materials like glass, wood, rubber metal, clay, leather and so on. b) These are cost effective and have better quality compared to their natural substitutes. c) They are more popular because their properties can be manipulated easily to suit the requirements.

Recycling of plastics Plastic is not decomposed by micro organisms. It is not biodegradable. Plastic waste cause pollution. It is very difficult to dispose them off. The pollution due to plastic waste can be prevented to some extent by recycling. Recycling is the process of using the material again by reprocessing Steps involved in recycling. 1) 2) 3) 4) 5)

Collection of waste plastic materials. Separating thermo setting and thermo plastic materials. Softening of thermo plastics Upgrading the quality by refining Re-moulding. 64

UDAYA English Medium High SCHOOL Std - X CEMENT Cement is a synthetic material. It is a mixture of calcium silicates, calcium Aluminate and gypsum (CaSO4) the ingredients required to manufacture cement are :1) Clay 2) Lime stone. Clay and Lime stone + H2O grounded well in a mortor. This gives a milky liquid called slurry. This slurry is made to run down through an inclined rotary kiln. Then a burning coal dust blast is projected in the opposite direction of motion of the slurry this heats up the slurry up to 1817 K. at this temperature slurry gets converted into hot tiny nodules of cement called clinkers. These clinkers are cooled and finely powdered. About 3% of gypsum is added to cement to to prevent the rapid setting of the cement. The cement manufactured is in grey colour which resembles the color of the houses in Portland therefore it is called as Portland cement.

Setting and Curing When water is added to cement it sets into a hard mass and acts as an excellent binding agent. When cement and sand are mixed with water it undergoes complex reaction and sets within 24 hours. It is more hardened or made to set still more, by adding water. The method of hardening of cement by treating it with water is called curing. In this process silicates and aluminates of calcium are converted in to a colloidal gel. This is an exothermic reaction therefore it requires continuous treatment of water.

GLASS Glass is a homogeneous mixture of sodium silicates and calcium silicates. Its molecular formula is (Na2SiO2.CaSiO3 4SiO2). Glass is called super cooled liquid, because even though glass attains solid state, the molecular of the glass behaves as the molecules of the liquid. The ingredients required to manufacture glass are:1) Sodium carbonate (Na2CO3) 2) Sand (Silica/SiO2)

3) Lime stone (CaCO3) 4) Scrap glass

The mixture is taken in proper proportion and put in an electric furnace and heated up to 1973 K at this temperature following reactions takes place. 65

UDAYA English Medium High SCHOOL Std - X Na2CO3 + SiO2 --- Na2SiO3 + CO2 CaCO3 + SiO2 ---- CaSiO3 + CO2 Thus a molten mixture of sodium and calcium silicon is formed. This is called glass. Molten glass is tapped out from the furnace and converted in to glass articles either by pouring in to moulds (moulding) or by blowing. Hot glass articles are cooled slowly to eliminate its brightness and to increase the strength of the glass. This process is called annealing.

Properties of Glass: It is strong and transparent material. It is corrosion resistant. It does not react with other chemical at ordinary temperature. It gradually softens on heating and begins to flow very slowly. The following table shows types of glass. Their properties and uses. Sl No Types Of Special Additive Glass 1 Soda glass aluminum

2

Borosilicate Boron

3

Lead glass

4

Colored glass

5

Safty glass

6

Fibres glass

Properties

Uses

Fuses easily at relative lowWindows panels temperature bottles , tumblers Withstand high Laboratory temperature fluctuation equipments

Led oxide Highly transparent, high Lenses, prisms potassium refractive index, absorbs windows penne's carbonate radiation nuclear installations Metal oxide Choice of metallic oxide is Window panels decided by the color to decorative be imparted materials Synthetic Withstand high stress, Windshields of plastic is sharp edges are not automobiles, sandwiched formed when it breaks bullets proof between two glass thin glass Molten glass is Light strong and fire proof Fire proof draw in to thin curtain and fibres and manufacture of sheets parts of prepared automobiles

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UDAYA English Medium High SCHOOL Std - X UNIT -19 WATER (H2O) The molecular formula of water in the liquid state is (H2O) Water available in the nature may be soft water or hard water. Sample of water which gives readily free lather with soap solution is called soft water. Ex- Rain water, Tap water etc. Sample of water which does not give readily free lather with soap solution is called hard water. Ex- Well water, boar water etc.

Hardness of water: There are two types of hardness of water – 1) Temporary hardness

2) Permanent hardness

Temporary hardness is due to the presence of calcium bicarbonate and magnesium bi carbonate Permanent hardness is due to dissolved salts like calcium chloride (CaCl 2) magnesium chloride (MgC12), calcium sulphate (CaSO4), and magnesium sulphate (MgSO4). Removal of Hardness of Water The process of removing the hardness of water is called softening of water The different methods of softening of water are 1) Boiling process 3) Clarkes process 5) Soda process 2) Permutit process 4) Ion exchange by resins method.

1. Boiling process Water having temporary hardness is taken in & boiled and heated to boil. The bi-carbonates of calcium and magnesium decompose and precipitate as their respective carbonates. Soft water is separated by the method of filtration. Ca (HCo3)2 BoilCaCo3 +H2O + Co2 Mg (HCo3)2 BoilMgCo3 + H2O + Co2

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UDAYA English Medium High SCHOOL Std - X 2. Clarkes process In this process required quantity of lime water – calcium hydroxide [Ca(OH)2] is added to water having temporary hardness. Bicarbonates of calcium and magnesium react with lime water and precipitate as their respective carbonates. Soft water is filtered off. Ca(HCo3)2 + Ca(OH)2 ---- 2CaCo3 + 2H2O Mg(HCO)2 + Ca(OH)2 --- MgCO3 + CaCO3 + 2H2O

3. Soda Process In this process a regulated quantity of amount of sodium carbonate (soda) is added to water having permanent hardness. Sodium carbonate reacts with chlorides and sulphate of calcium and magnesium and precipitates them as their respective carbonates. Soft water is separated by filtration. The reactions can be shown as follows: CaCl2 + Na2Co3 - CaCo3 +NaCl MgCl2 + Na2Co3 - MgCo3 +2NaCl CaSo4 + Na2Co3 -- CaCo3 + Na2So4 MgSo4 + Na2Co3 - MgCo3 + Na2So4

4. Permutit Process Permutit is the trade name given to the Zeolite. It is called Sodium Alluminium Silicate. Its formula is Na2Al2Sio2. This is also called as Sodium Permutit. When hard water is passed through a column of Zeolite the Nations of Zeolite exchanges with Ca++ and Mg++ cautions of permanent hard water. This produces soluble chlorides and sulphates rendering the water soft. Soft water raises up in the tower and it taped out. The reaction between the permutit and chlorides and sulphates of calcium and Magnesium can be shown as follows: Na2Al2SiO8 + CaCl2 --- CaAl2SiO8 + 2NaCl Na2Al2SiO8 + MgCl2 --- MgAl2SiO8 + 2NaCl Na2Al2SiO8 + CaSO4 --- CaAl2SiO8 + Na2SO4 Na2Al2SiO8 + MgSO4 --- MgAl2SiO8 + 2Na2SO4 In this process there is no need to add permutit to the tower again and again to soften the water repeatedly. The tower can be regenerated to produce sodium permutit by adding hot brine solution – 23% of NaCl. CaAl2SiO8 + 2NaCl --- Na2Al2SiO8 + CaCl2 MgAl2SiO8 + 2NaCl --- Na2Al2SiO8 + MgCl2 This process is very economical as only the sodium chloride is consumed. Permutit is a synthetic form of Zeolite. Naturally occurring mineral of Permutit is called Calgon.

5. Ion exchange by Resins In this process synthetic resins of the type R-SO3H, R-COOH type, R-NH3 type are used, where R is called Alkyl Radical (Methyl, Ehtyl, propile etc). these radicals exchange cations like Ca++ and Mg++ and anions like Cl and SO4 separately in different columns. Thus we get deionised soft water. Ex: When hard water passed through cation exchange Ca++ Mg++ are exchanged and large amount of hydrogen ion – H+ ions are formed. The reaction can be shown as follows. 68

UDAYA English Medium High SCHOOL Std - X 2R – H + Ca++ --- R2Ca+2H+ 2R – H + Mg++ --- R2Mg+2H+ Water coming out of caution exchanger is highly acidic because of the presence of hydrogen ions. This water is passed through a synthetic resin bed of anion exchanger where Cl - & So4++ anions are exchanged with the formation of hydroxide ions (OH—ions ). The reactions are : R – OH +Cl ---R-Cl+OH2R-OH + So4-- --- R-So4+2OHThe liberated hydroxide ions neutralie the hydrogen ions and gives deionised soft water. + H +OH- --- H2O (Deionised soft water). This method also works on regenerative system. The cation exchange can be regenerated by adding Hydrochloric acid or suplhuric acid. The anion exchange can be regenerated by adding sodium hydroxide.

Conservation of water. About 71% of the earth is covered with water. Out of this 3% of water is fresh water. Out of this 3%, 2.5% of water is locked in the form of ice, only about 0.5% of fresh water is available through all the rivers, lake and pounds for Sustaining all forms of life on earth, also this water is used for industrial and agricultural process.

Ground water is exhausting due to: 1) Rapid rate of use of water. 2) Unconrolled increase in the number of tube-wells. 3) Increase in the rate of evaporation. 4) Deforestation. a) Results in the decreasing the capacity if earth to hold water. b) IT has reduced averrage annual rainfall. Thus it is needed to have awareness in the usage of water and to conserve it.

THE VARIOUS MEANS OR METHODS OF CONSERVING WATER: 1) Water should be used economically avoiding all possible wastages. 2) Pollution of water should be minimized by various methods. 3) House hold wastage, municipal wastes, and industrial wastes must be discharged into lakes, ponds, rivers and canals. 4) Open well must be discouraged. 5) Planning of small dams or reservoirs around township without destroying vegetation helps in sustained and continuous water supply. 6) Various methods of rain water harvesting should be adopted. 7) Adverse effect of deforestation should be reversed by massive afforestation schems. 8) Affluent treatment plants should be installed in different industries. 9) Bore-wells are to be avoided. 10) Adequate recycling water and using it for various purpose helps in conservation of water not only for ourselves but also for the future generations. 69

UDAYA English Medium High SCHOOL Std - X UNIT -19 SOAPS AND DETERGENTS DETERGENTS : Any substance which has cleansing action in water is called detergent. The two cleansing substances are : 1) Soapy – Soap 2) Non soapy – detergent – synthetic detergent. SOAPS AND DETERGENTS are sodium salts of different organic acids. They are used for washing clothes, shampoos (hair), cleaning utensils, and textile manufacturing.

SOAP : Soap in the sodium salt of a long chain of carboxylic acid, which has cleansing property in water. It has large nonionic hydrocarbon group and an ionic group. Ex. Sodium steorate C17H35COO- Na+ Sodium oleate C17H33COO- Na+ Sodium Pelimitate C17H31COO- Na+ Ex: A long chain of Benzene sulphoni acid reacts with sodium hydroxide it forms sodium salt of Benzene sulphoni. 1. [CH3 –(CH2)n +O –SO3-Na+] (Benzene Sulphonate comman synthetic detergent ) Synthetic detergents are prepared by heating long chain of hydrocarbon obtained from petroleum with sulphuric acid. This forms Hydrocarbon sulphonic acid. This acid no neutralizing with NAOH forms a detergent. 1. CH3 -(CH2)n –CH3 + H2SO4 ---- CH3 -(CH2)n –H2SO3H+ +H2O 2. CH3 -(CH2)n –CH2SO3H+ +NaOH --- CH3 -(CH2)n –CH2SO3- +Na+ +H2O Action of hard water with detergents : Hard water consists of salts of calcium and magnesium when these salts react with detergent solution calcium and magnesium salts of hydrocarbon are formed. These are readily soluble in solution. Therefore more lather formed and it removes the dirt in the clothes .Thus detergents are preferred to wash the clothes with hard water. Manufacturing The main material required in manufacture of soap are 1) Animal fat 2) Vegetable oil 3) An Alkali NaOH 70

UDAYA English Medium High SCHOOL Std - X Soap is manufactured by heating animal fat or vegetable oil with concentrated sodium hydroxide solution. The fat or oil reacts with NaoH to form soap and glycerol. The process of making soap by the hydrolysis of fats and oils with an alkali is called saponification. Action of soap with hard water. When the soap solution reacts with hard water the salt of magnesium and calcium forms calcium stearate which are insoluble in solution. Therefore a thick white sum is produced which is nothing but wastage of soap therefore ordinary soap is not preferred to clean clothes with hard water. Detergents: Synthetic detergents is a sodium salt of a long chain of hydrocarbon obtained from petroleum product and has cleansing action with water.

Difference between Soaps and Detergents 1

Soaps Detergents Soaps are the sodium salts of long chain of 1 Synthetic detergents are the sodium salts carboxylic acids of long chain of Benzene sulphuric acids. 2 These have ionic group SO3 Na+ 3 These can be used for washing even when water is hard.

2 3

These have ionic group Coo-Na Soaps are not suitable to wash with Hard water.

4

Soaps are not suitable from vegetable oil 4 Detergents are prepared from long chain or animal fat. of hydrocarbons of petroleum

5

Soaps are bio degradable

5 Some of the biodegradable

6

Soaps have relatively weak cleaning action

6 Synthetic detergents cleaning action

detergents have

are a

nonstrong

Hard water is not used in the industrial boilers. Give reason. Reason: 1. The salts that deposits on the inner walls of the boiler reduced the efficiency of boiler. 2. The salts that deposits on the inner walls of the corrodes the boiler and damages.

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