10TH SCIENCE 2MARKS

•                                          SCIENCE TWO MARK QUESTIONS
•                                            1. Heredity and Evolution
• 1. Mendel has observed Tallness as a dominant character in the garden pea plant. Similarly, tongue rolling is a
• dominant character in man. In a group of 60 students, 45 can roll their tongue and 15 are non-rollers.
• i) In the above context, calculate the percentage of dominant and recessive characters.
• 2. The inheritable characters vary in different species and within the same species.
• Name the variation in the following cases.
• The eye colour among the human beings are varied as blue, black, brown, green, etc.
• i) This is called as _______variation.
• The dentition in the rabbit and the elephant are not the same.
• ii) This is called as __________ variation.
• 3. Sexually reproducing organisms produce offspring with marked, significant and visible variation. Asexually
• reproducing offspring show minor variations.
• i) Do you agree with the above statements?
• ii) Among the following organisms point out the asexually reproducing organism.
• (Cockroach, Euglena, Earthworm and Bird)
• 4. Here are certain important hereditary jargons. Fill in the blanks by choosing a suitable one from the list given.
• (allele, variation, speciation, gene, allelomorphs)
• i) __________ are the factors which form the physical basis of inheritance.
• ii)__________ is the alternate forms of the same gene.
• iii)__________ are the expressions of contrasting pair of alleles.
• 5. A change that affects the body cell is not inherited. However, a change in the gamete is inherited. The effects of
• radiation at Hiroshima have been affecting generations. Analyze the above statements and give your
• interpretation.
• 6. Sequentially arrange the different species of man from primitive to modern man.
• (Neanderthal man, Homo habilis, Homo erectus, Homo sapiens)
• 7. Biotechnology, the modern science in biology, has helped in producing different types of products.One of the
• following groups does not have a product of biotechnology. Pick out and give reasons.
• i) enzymes, organic acids, steroids, vaccines
• ii) vaccines, enzymes, antibiotics, inorganic acids
• iii) antibiotics, hormones, steroids, vaccines
• iv) steroids, enzymes, antibodies, vaccines.
• 8. What do you mean by phenotype and genotype of an individual? Explain.
• 9. What are variations? Mention their types.
• 10. Who proposed the theory of Natural Selection? Mention the two principles of this theory.
• 11. What are monoclonal antibodies? Mention its use.
• 12. What is a clone? In what way is the cloning technique useful in the field of veterinary science?
• 13. In dogs, the barking trait is dominant over the silent trait. Using Punnet Square, work out the possible
• puppies born to two barking parents with genotype (Rr).
• 14. In Dr. Ian Wilmut’s cloning experiment, did the new born 'Dolly' resemble the udder cell donor Dorset white
• sheep or the surrogate mother sheep? Give reasons.
• 15. The excessive use of pesticides has only resulted in the occurrence of more resistant varieties of pests rather
• than their complete eradication. How can you link this with Darwin’s theory of Natural Selection and
• Evolution?
• 16. The first clinical gene therapy was given in 1990 to a four year old girl suffering from Adenosine Deaminase
• Deficiency (ADA) . Could you suggest a possible cure for such a disorder with the knowledge of gene therapy
• and its types?
• 17. Find the unmatched pairs:
• 18. For the experimental research Dr.Ian Wilmut used the nucleus of the udder cell from a six year old Finn
• Dorset white sheep and preserved the diploid nucleus (2n). He took an ovum from the ovary of another
• sheep. The haploid ovum was removed. The diploid nucleus of the udder cell was injected into the cytoplasm
• of the enucleated ovum. Then the diploid nucleus ovum was implanted into the uterus of the surrogate
• mother sheep. The diploid ovum developed into a young one, named “Dolly”.
• i) Why did Wilmut select the udder cell?
• ii) Define the terms haploid and diploid.
• 19. Match the following by identifying the pair :
• (medicines, fuel, microbes, metabolism, organic acids)
• i) vaccine ii) natural gas iii) citric acid iv) monoclonal antibodies v) vitamins
• 20. Mention the dominant and recessive traits observed by Mendel in the garden pea plant with respect to the
• seed and flower.
• 2. Immune System
• 1. Marasmus and Kwashiorkar are both protein deficiency defects. Marasmus differs from Kwashiorkar in enlarged
• belly and swelling in the face. Are these symptoms for the above diseases correct? If not, correct it.
• 2. A list of disorders are given below. Pick out the odd one out and give reasons.
• (Thalassemia, haemophilia, night blindness, albinism, sickle cell anaemia)
• 3. What are the symptoms of common cold?
• i) ____________________ ii) ____________________
• 4. Differentiate between the diseases-night blindness and colour blindness.
• 5. After observing dark patches with itching sensation on the skin of a student in a school hostel, the warden advises
• his room mates not to share towels, clothes and combs among themselves. Name the disease the student is
• suffering from and name the causative organisms.
• 6. Name the vector host of the malarial parasite. Mention the species of malarial parasite which causes malignant and
• fatal malaria.
• 7. Name the tests done for the diagnosis and confirmation of AIDS.
• 8. What is triple antigen? Name the three diseases which, can be prevented by using it.
• 9. Mention the type of immunity acquired by a baby through breast-feeding.
• 10. Study the following statements and state whether they are true or false.
• i) Colour blindness is a genetic disorder, whereas night blindness is a nutritional disorder.
• ii) Pernicious anaemia is a nutritional deficiency disease, whereas sickle cell anaemia is a genetic disease / disorder.
• iii) Administering TT injection to an injured child is related to passive artificial immunity, whereas giving BCG
• vaccine is active artificial immunity.
• iv) Malaria is a bacterial disease, whereas ring worm is a viral disease.
• 11. Ramya is suffering from bleeding gums and loosening teeth. On diagnosis, it was found to have been caused by
• vitamin deficiency.
• Tell Ramya the vitamin that is lacking in her food ___________ , the name of deficiency disease she is suffering from
• ___________ .
• 12. Match B and C with A:
• 13. A health worker advises the people in a locality not to have tattooing done using common needles and to insist the
• barber to change the shaving razors/ blades in the salon. Name the dreadful disease, the spreading of which, can
• be prevented by following these measures. Also mention other preventive measures that can be taken with regard
• to this disease.
• 14. Match the following:
• 15.List out the diseases based on their mode of transmission (water borne, air borne, sexual contact)
• i) cholera ii) typhoid iii) tuberculosis iv) leprosy v) syphilis
• vi) gonorrhoea vii) pneumonia viii) common cold ix) amoebic dysentery x) AIDS
• 16. i) Give any three examples for the most infectious diseases in man and their causative agents.
• ii) To discover medicine for viral infected diseases like AIDS is more difficult than other diseases. Is the statement
• true or false? Discuss.
• 17. A student had an attack of measles and recovered from the infection. His science teacher said that he will not get
• that disease again in his life time. Is it true? Why?
• 18. Name the causative organisms responsible for ring worm in humans? Mention the symptoms of the infection.
• 19. Pick out the odd ones:
• i) AIDS : Retro virus, lymphocytes, BCG, ELISA
• ii) Bacterial disease : Rabies, cholera, common cold, influenza
• iii) DPT vaccine : Diphtheria, tuberculosis, pertusis, tetanus
• iv) Infective stage of Plasmodium in humans : Sporozoites, merozoites, trophozoites, gametocytes.
• v) Mental dimension : brightness of skin, normal metabolism, no black rings around eyes, knows his capacity.
• 20. In the manufacturing of anti-venom injection against snake bite, antibodies produced in the horse are being used.
• Mention the type of immunity involved.
• 21. Say whether each of the following diseases is a metabolic disorder, a genetic disorder or a nutritional deficiency
• disease.
• i) thalassemia ii) beriberi iii) diabetes mellitus iv) bubble boy syndrome v) scurvy
• vi) marasmus vii) obesity viii) Alzheimer’s disease ix) nyctalopia x) haemophilia
• 22. Find the correct statement (True / False) :
• i) Tuberculosis is caused by Mycobacterium tuberculosis bacteria.
• ii) Typhoid is caused by Trichophyton fungi.
• iii) Malaria is caused by Plasmodium vivax.
• iv) Influenza is caused by Entamoeba histolytica protozoan.
• 23. Malarial fever is not caused in a person immediately after introducing the sporozoites by an infected anopheles
• mosquito. Why?
• 24. Name the stages of Plasmodium.
• i) introduced by an infected Anopheles mosquito.
• ii) picked up by Anopheles mosquito from an infected human being.
• 25. Name two diseases that are transmitted by houseflies. Mention their causative pathogens.
• 26. Observe the following flow-chart
• Mention the metabolic disorder ‘X’ and the causative factor from the options given below:
• Mention the metabolic disorder ‘X’ and the causative factor from the options given below:
• 3. Structure and Function of Human Body Organ System
• 1. Name the two systems which help in the control and co-ordination of metabolic activities. Write any one difference
• between them.
• 2. Differentiate medullated neurons from non-medullated neurons. Where are they found in the nervous system?
• 3. Name the part of the brain which regulates heart beat and respiration. Where is it located in the brain?
• 4. What is corpora quadrigemina? Name the functions associated with it.
• 5. What are endocrine glands? Name the secretions of these glands. How do these secretions reach the target organs?
• 6. Name the following endocrine glands:
• i) The master of endocrine orchestra ii) The dual gland
• 7. Which hormone(s) is/are called i) Personality hormone ii) fight, flight and fright hormones.
• 8. Name the male and female sex hormones. List out their functions.
• 9. In which sub-stages of meiosis-I do the following events occur?
• i) pairing of homologous chromosomes ii) terminalization
• iii) crossing over iv) formation of spindle apparatus.
• 10. Copy the diagram and label any two parts in the group given:
• (cyton, axon, dendron, terminal branches)
• 11. The diagram is of the human brain. Shade the areas marked A and B in the parts of the brain, corresponding with
• the function.
• A. Seat of smell B. Seat of vision
• 12. On the basis of the function performed, pick out the right statements.
• i) Pituitary gland secretes hormones and enzymes.
• ii) Thyroid gland secretes thyroxine and insulin.
• iii) Leydig cells produce testosterone hormone.
• iv) Pancreas produces enzymes and hormones.
• 13. Correct the statements, if they are wrong.
• i) Alpha cells produce insulin and beta cells produce glucagon.
• ii) Cortisone suppresses the immune response.
• iii) Thymus gland is a lymphoid mass.
• iv) Ovary produces eggs and androgen.
• 14. Here are a few statements about the endocrine system in man. State whether each of them is true or false. If the
• statement is false write the correct statement.
• i) Endocrine system controls and co-ordinates the physical process of growth, reproduction and sustenance of life.
• ii) Endocrine glands are duct bearing glands which secrete chemical substances called hormones.
• iii) The pancreas is a dual gland.
• iv) Malfunctioning of the thymus gland causes goitre.
• 15. Copy and complete the following table:
• 16.Copy the diagram and label the parts with the help of the clues given:
• i) It is otherwise called supra renal gland.
• ii) It secretes two hormones, namely aldosterone and cortisone.
• 17. Copy and identify the types of neurons given below:
• 18. Here are some statements about meiosis. State whether each of them is true or false:
• i) It takes place in somatic cells.
• ii) Meiosis is also called reduction division.
• iii) Pairing of homologous chromosomes is called crossing over.
• iv) Meiosis leads to variations which form the raw material for evolution.
• 19. Match the following:
• A.
• 20. A person was riding a two-wheeler without wearing a helmet. He met with an accident and sustained a head
• injury. He was dead before he was shifted to the hospital and it was found that his death was due to
• breathlessness and heart failure. Which part of his brain might have been damaged? Justify your answer.
• 21. Match the following:
• 22. Observe the following diagrams that depict the transmission of nerve impulses through two pathways from body
• parts to CNS:
• If all the nerves at both the places are similar in thickness and structure, through which pathway will the
• transmission of an impulse (of same threshold) be faster and why?
• 23. Which gland is called the ‘dual gland’? Why?
• 24. A 16 year old boy was brought to a doctor with a complaint of non-masculine features (lack of moustache / beard
• / gruff voice / broadening of shoulders etc). After keen examination, the doctor found that it was a hormonal
• disorder and the endocrine glands responsible were not functioning properly. Mention the glands and the
• hormone lacking in the boy.
• 4. Reproduction in Plants
• 1. Write any two differences between asexual and sexual modes of reproduction.
• 2. What is vegetative propagation? Mention the vegetative propagules in:
• i) Bryophyllum ii) Sprirogyra
• 3. Arrange the following events of sexual reproduction in plants in the correct sequential order :
• seed formation, pollination, dispersal of seeds, fertilization.
• 4. Define pollination.
• 5. Define fertilization.
• 6. Name the agents of pollination in the following cases:
• i) Bright coloured flowers with scent and nectar glands.
• ii) No colour / scent/ nectar but pollen grains are dry, light weight and powdery. Stigma is feathery.
• Also mention the plants in cases (i) & (ii).
• 7. Name the events (i) & (ii) and mention the nature of the nuclear structures formed at the end in the following cases:
• (i) male gamete (n) + egg (n) = Zygote (2n)
• (ii) male gamete (n) + secondary nucleus (2n) = Endosperm nucleus (3n).
• 8. Differentiate dehiscent fruits and indehiscent fruits with suitable examples.
• 9. What are monocotyledons and dicotyledons? Give examples.
• 10. Give suitable terms for the following methods of seed / fruit dispersal, with one example each:
• (i) by wind (ii) by water (iii) by animals.
• 11. Give any two examples for each of the following cases where dispersal of fruits and seeds take place :
• (i) by birds (through excreta) (ii) by human beings
• 12.What is double fertilization?
• 13. What is triple fusion?
• 14. a) Identify Fig. A and B. b) Which part of A is modified into B.
• 15. The methods of reproduction and the organisms are given below. Match the type of reproduction with the suitable
• organism.
• 16. i) Composite fruits are formed by all the flowers of _________,
• ii) _________ fruit is developed from a single flower with a multicarpellary apocarpous superior ovary.
• 17. Draw the given diagram and label the following parts:
• i) Exine ii) Tube nucleus.
• 18. Match the following with respect to dispersal of fruits / seeds:
• 19. Use words from the given list to complete the following paragraph. (The words may be used once / more than
• once / not at all).
• (seed, fruit, pollination, dispersal, germination, fertilization, flower, reproduction)
• Ramu went to the field along with his father. He sowed mustard seeds in the soil. After a few days he observed the
• process of ________ . The seeds grew into plants and produced ________. On maturity, these flowers produced pollen
• grains that were transferred to the stigma by ________ . The male gametes fused with the female gametes during the
• process of ________ .
• 20. Coconut seeds are dispersed by Hydrochory (dispersal by water). Mention the part of the fruit whose modification
• help in this mechanism.
• 5. A Representative Study of mammals
• 1. Mention the two unique characteristics of mammals.
• 2. Give two examples each: (i) ruminating mammals (ii) marine mammals.
• 3. What type of dentition is seen in mammals? What are elephant tusks?
• 4. Mention any four adaptations seen in the camel so that it can live successfully in deserts.
• 5. What is echo location? Give an example.
• 6. Mention the various valves and their location in the human heart.
• 7. Write any four differences between arteries and veins in mammals.
• 8. Name the three important blood proteins seen in plasma. Add a note on their functions.
• 9. Which blood cells are without nuclei? What is the advantage of this condition?
• 10. Name the protein and the blood-cells responsible for the clotting of blood.
• 11. i) What are the structural and functional units of kidney?
• ii) Arrange the organs of the human excretory system in the correct order, based on the passage of urine.
• Ureter, Urethra, Kidney, Urinary bladder
• 12. Observe the following flow-chart depicting blood-circulation in mammals.
• Pick out the correct blood vessels A,B,C,D from the following:
• i) Pulmonary veins ii) Venacava iii) Pulmonary artery iv) Aorta
• Among the P,Q,R and S samples, identify the correct match from the following
• a) P & Q = Oxygenated and R& S = Deoxygenated
• b) P & Q = Deoxygenated and R& S = oxygenated
• c) All are Oxygenated
• d) All are Deoxygenated
• 13. Study the following passage:
• Most of the vertebrates have jaws with teeth. The mode of arrangement of teeth on the jaws is called dentition.
• The various types of teeth seen in mammals are incisors(I) canines (C) premolars (P) and molars (M). They are
• used for biting , tearing, chewing and grinding respectively. Canines, the tearing teeth are well-developed in
• carnivores and ill-developed or absent in herbivores.
• Now answer the following questions:
• i) In frogs, all the teeth in the upper jaw look alike, whereas in human beings they are different. The type of
• dentition in man can be called__________.
• a) Homodont b) Isodont c) Heterodont d) Acrodont
• ii) The dental formula of a mammal is written as ICPM =2023/1023. The teeth missing in it are _________ .
• a) incisors b) canines c) premolars d) molars
• 14. Fill in the empty boxes with suitable answers with respect to the valves of a mammalian heart.
• 15. Any change in the lifestyle, the food habits and the body form of an organism in order to make it comfortable in
• the environment / habitat, is called adaptation. Identify the suitable adaptation given below against each mammal.
• i) conservation of body heat in large marine mammals like whale (Jaws are modified into baleen plates /
• Forelimbs are modified into flippers / Fat is deposited in subcutaneous tissue.)
• ii) Locating food source by bats-( Forelimbs are modified into wings / Hanging upside down using legs /
• Production of sounds and detection of the echo)
• 16.The Master chemists of our body are the kidneys. Justify.
• i) Kidneys filter all chemicals in the body.
• ii) Kidneys maintain the chemical composition of blood.
• iii) Kidneys eliminate all chemicals absorbed by the body.
• iv) Kidneys store the chemicals accumulated in the body.
• 6. Life Processes
• 1. Name the types of vascular tissues in the plant stem which are labelled A and B.
• 2. What is nutrition? What type of nutrition is seen in green plants and the majority of animals?
• 3. Match the methods of nutrition of special organs with suitable examples:
• 4. Observe the diagram
• i) Mention the type of movements shown in figure A and B.
• ii) How does this movement differ from the movement of mimosa?
• 5. In the process of anaerobic respiration, _____ is a 6 carbon compound which gets converted into ________carbon
• compound called lactic acid.
• 6. Sugar is converted into alcohol. In the above reaction what kind of process takes place? Which micro-organism is
• involved?
• 7. In human beings, air enters into the body through _________ and moves into __________. In fishes, water enters into the
• body through _________ and the dissolved oxygen diffuses into _________.
• 8. Give two examples of root parasites of plants. Mention the special structures present in them to draw the nutrients
• from the host plant.
• 9. What are saprophytes? Give two examples.
• 10. What is the length of the alimentary canal in human beings? List out the parts of the gastro-intestinal tract in the
• correct sequential order based on the passage of food.
• 11. What is respiration? Give a balanced equation for aerobic respiration.
• 12. A fish taken out of water can not survive for a long time. Why?
• 13. What are ammoniatelic and ureotelic animals? Give examples.
• 14. Describe the change that occurs in a touch-me-not plant when it is touched?
• 15. Study the following model with which the transpiration mechanism in plants can be demonstrated
• With which structure of the plant do you compare each of the following?
• (i)Sponge (ii) Glass tube filled with water.
• 7. Conservation of Environment
• 1. Classify the following into producers, consumers, decomposers.
• i) butterfly ii). grass hopper iii) calottes iv) snakes v) shoe flower vi) nitrobacteria
• 2. Living organisms adapt themselves according to their habitat.
• Match the following:-
• 3. Fill in the blanks
• i) Animals give out __________ through respiration.
• ii) In the presence of sunlight, plants prepare _________.
• 4.`Bacteria and fungi are responsible for the decay of dead plants and animals. Decaying matter is recycled to grow
• plants. What do we call this?
• 5. Fill in the blanks with suitable answers from those given in the brackets.
• (harmful, heavy metals, carbon dioxide, sulphur particles)
• Generation of waste products which contain Mercury, Uranium, Thorium, Arsenic, and other ________ are _______ to
• human health and environment. _______ present in the coal will cause acid rain and the release of _________, a green
• house gas, causes climate change and global warming.
• 6. Depict a food chain by placing the following organisms in the correct trophic levels:
• (snake, grass, eagle, frog, grasshopper)
• 7. Show an aquatic food chain using the following organisms.
• (Small fish, Phytoplanktons, Kingfisher, Zooplanktons)
• 8. Observe the following food web:
• (i) Find out the wrong statement:
• a) ‘A’ is a producer b) ‘F’ is a herbivore c) ‘H’ is an omnivore d) ‘I’ is a climax carnivore
• (ii) Find out how many food chains are present in the above food web.
• 9. Observe the following Bio-geo chemical cycle.
• i) Mention the nutrient in the given cycle.
• ii) Write the activities from‘A’ to ‘D’.
• 10. Study the food chain below, correct it and convert it into a pyramid of energy.
• Mulberry -> Sparrow -> Caterpillar -> Kite
• 11. Study the illustration and answer the questions:
• i) Which line (A or B) represents the flow of energy? Why do you say so?
• ii) Give an example of a decomposer.
• 12. i) Name the processes noted as No. 1 and 3.
• ii) Define process 1.
• 8. Waste Water Management
• 1. The bar-graph indicates the prevalence / widespread attack of infectious diseases in two cities A and B. Observe it
• and answer the questions given below:
• 1. Dengue fever 2. Rat fever 3. Cholera 4. Chikungunya
• a. What may be the reason for the disease in city A?
• b. Which city needs more effective system of waste-disposal and cleaning?
• c. How can the disease be controlled in city A?
• 2. The pie diagram represents a survey result of infectious diseases in a village during 2008 – 2009. Analyse it and
• answer the following:
• i) Which diseases affect the majority of the population?
• ii) How are these diseases transmitted?
• iii) Mention any three measures that can control the other two diseases.
• 3. Match the suitable renewable and non-renewable sources.
• 4. Find the odd one out:
• i) bioalcohol, green diesel, bioethers, petroleum
• ii) cholera, typhoid, scabies, dysentry
• 5. A non-renewable resource is a natural resource, if it is replaced by natural process at a rate equal to or faster than
• its rate of consumption by humans. Read this statement and say whether it is correct or incorrect. If it is incorrect,
• give the correct statement.
• 6. Pick out the appliances that can conserve electric energy.
• Florescent bulbs, copper choke, solar water heater, electric water heater, tungsten bulbs, electronic choke.
• 9. Solutions
• 1. From the table given below, furnish your points of inference.
• 2. Distinguish between the saturated and unsaturated solution at a temperature of 25oC using the data given below
• (Note : Solubility of NaCl is 36g)
• i) 16g NaCl in 100g water ii) 36g NaCl in 100g water
• 3. Differentiate true solution and colloidal solution.
• 4. You have prepared a saturated solution of sugar at room temperature. Is it possible to dissolve some more grams of
• sugar to this solution? Justify your answer.
• 5. Find the concentration of solution in terms of weight percent if 20g of common salt is dissolved in 50g of water.
• 6. Valli took some common salt, naphthalene balls, camphor, baking soda and washing soda. She attempted to dissolve
• these substances either in water or in acetone. Complete the table with the expected results.
• 7.
• i) Which gas is dissolved in soft drinks?
• ii) What will you do to increase the solubility of this gas?
• 8. Beaker A has sugar mixed with water and Beaker B has starch dissolved in water.
• i) Which solution will scatter light?
• ii) In which beaker does the Brownian movement take place?
• iii) Name the type of solution that beaker A and beaker B contain.
• iv) Which of the two solutions is homogeneous?
• v) Identify the beaker that has particles of size 10 AO to 2000 AO.
• 9. Name the type of solution formed in the following cases:
• i) 20g of NaCl in 100g of water. ii) 36g of NaCl in 100g of water. iii) 45g of NaCl in 100g of water at 80°C.
• iv) Sulphur dissolved in CS2 v) Nitrogen in soil.
• 10. Give the dispersed phase and the dispersion medium in each of the following:
• a. cheese b. soda water c. smoke
• 11. Radha prepared a solution which could be separated by filtration.
• i) Name the type of solution.
• ii) Is the solution transparent or opaque?
• iii) Mention the nature of the solution.
• iv) Mention the size of the solute particle.
• 12.
• In the above case, Sekar observed that the water turned sweeter after sometime. Explain the reason for the same.
• 13. Beaker ‘A’ has chalk powder mixed with water and beaker ‘B’ has protein dissolved in water.
• i) Which solution shows Brownian movement?
• ii) Identify the solution that has particle size greater than 2000AO.
• iii) Which beaker contains colloidal solution?
• iv) Mention the size of the particle present in beaker B.
• v) Say whether colloidal solution is homogeneous or heterogeneous.
• 14. Justify the following statements with an explanation:
• i) Solubility of calcium oxide decreases with increase in temperature.
• ii) What happens to the solubility in exothermic process with regard to temperature?
• iii) In endothermic process, solubility increases with increase in temperature.
• iv) At a given temperature, increase in pressure increases the solubility of the gas.
• 10. Atoms and Molecules
• 1. Modern atomic theory takes up the wave concept, principle of uncertainty and other latest discoveries to give a
• clear cut picture about an atom. State the findings of modern atomic theory.
• 2. How will you establish the relation between vapour density and molecular mass of a gas by applying Avogadro’s \
• law?
• 3. Calculate the number of moles in:
• i) 12.046 x 1023 atoms of Copper ii) 27.95g of Iron iii) 1.51 x 1023 molecules of CO2
• 4. Find the gram molecular mass of the following from the data given:
• i) H2O ii) CO2 iii) NaOH iv) NO2 v) H2SO4
• 5. Complete the table given below:
• 6. Calculate the number of water molecules present in one drop of water which weighs 0.18 g.
• 7. Fill in the blanks using the given data:
• The formula of Calcium oxide is CaO. The atomic mass of Ca is 40, Oxygen is 16 and Carbon is 12.
• i) 1 mole of Ca ( ____g) and 1 mole of Oxygen atom ( ___g) combine to form _____ mole of CaO ( ____g).
• ii) 1 mole of Ca ( ___g) and 1 mole of C ( ___g) and 3 moles of Oxygen atom ( ___g) combine to form 1 mole of CaCO3
• ( ___g)
• 8. How many grams are there in:
• i) 5 moles of water ii) 2 moles of Ammonia iii) 2 moles of Glucose.
• 11. Chemical reaction
• 1. What type of chemical reaction takes place when i) limestone is heated? ii) A magnesium ribbon is burnt in air?
• 2. The pH values of certain familiar substances are given below:
• Analyse the data in the table and answer the following questions:
• i) Which substances are acidic in nature?
• ii) Which substances are basic in nature?
• 3. Why does the colour of copper sulphate change when an iron nail is kept in it? Justify your answer.
• 4. The hydroxide ion concentration of a solution is 1.0 x 10 –8M. What is the pH of the solution?
• 5. Equal lengths of magnesium ribbons are taken in test tubes A and B. Hydrochloric acid is added to test tube A, while
• acetic acid is added to test tube B. The amount and concentration taken for both the acids are same. In which test
• tube does the reaction occur more vigourously and why?
• 6. Two acids ‘A’ and ‘B’ were kept in beakers. Acid ‘A’ undergoes partial dissociation in water, whereas acid ‘B’
• undergoes complete dissociation in water.
• i) Of the two acids ‘A’ and ‘B’ , which is weak acid and which is strong acid?
• ii) What is a weak acid?
• iii) What is a strong acid?
• iv) Give one example each.
• 7. Observe the given chemical change and answer the following:
• i) Identify ‘A’ and ‘B’. ii) Write the commercial name of calcium hydroxide.
• iii) Identify products ‘C’ and 'D' , when HCl is allowed to react with calcium oxide.
• iv) Say whether calcium oxide is acidic or basic.
• 8. Take copper nitrate in a test tube and heat it over the flame.
• i) What is the colour of cupric nitrate? ii) What do you observe?
• iii) Name the type of reaction that takes place. iv) Write the balanced equation.
• 9. Identify the wrong statements and correct them.
• i) Sodium benzoate is used in food preservative. ii) Nitric acid is not used as fertilizer in agriculture.
• iii) Sulphuric acid is called the king of chemicals. iv) The PH of acid is greater than 7.
• v) Acetic acid is used in aerated drinks.
• 10. Redox reactions are reactions during which electron transfer takes place. Here magnesium atom transfers two
• electrons one each to the two chlorine atoms.
• i) What are the products of this reaction? ii) Write the balanced equation for the complete reaction.
• iii) Which element is being oxidized? iv) Which element is being reduced?
• v) Write the reduction part of the reaction.
• 11. Suggest a reason for each observation given below.
• i) In fireworks, powdered magnesium is used rather than magnesium ribbon.
• ii) Zinc and dilute H2SO4 react much more quickly when a few drops of copper sulphate solutions are added.
• iii) The reaction between magnesium carbonate and dilute hydrochloric acid speeds up when some concentrated
• HCl is added.
• 12. Sodium hydroxide and hydrochloric acid react as shown in this equation.
• i) Which type of chemical reaction is this?
• ii) The reaction is exothermic. Explain what that means.
• iii) Differentiate exothermic reaction and endothermic reaction.
• iv) What happens to the temperature of the solution as the chemicals react?
• 13. Take two conical flasks. Label them as I and II. Take a small amount of copper sulphate solution in the first conical
• flask. Take a small amount of granulated zinc in the second conical flask. Allow the copper sulphate solution to
• react with the zinc.
• i) Name the type of reaction. ii) Say whether the metal zinc is more reactive or less reactive.
• iii) Write the complete and balanced reaction. iv) Say whether this change is reversible or irreversible.
• 14. Relate the information given in all the four columns of the table.
• 15. When lead powder is added to copper chloride solution, a displacement reaction occurs and solid copper is
• formed.
• i) Write the equation for the reaction. ii) Why does the displacement reaction occur?
• 16. When zinc and copper (II) sulphate are heated together, the following redox reaction occurs:
• i) What does the word redox stand for?
• ii) Show how electrons are transferred in the reaction.
• iii) Write the ionic equation for the redox reaction.
• 17. If a substance gains oxygen during a reaction, it is being oxidized. If it loses oxygen, it is being reduced. Oxidation
• and Reduction always take place together, so that if one substance is oxidized, another is reduced. Using this idea,
• say which substance is oxidised and which substance is reduced in each reaction.
• 18. The hydrogen ion concentration of a solution is 1 X 10 -8 M
• i) What is the PH of the solution?
• ii) What is the POH of the solution?
• iii) Is the given solution, acidic or basic?
• 12. Periodic Classification of Elements
• 1. Assertion: A greenish layer appears on copper vessels, if left uncleaned.
• Reason: It is due to the formation of a layer of basic copper carbonate
• Give the correct option:
• i) Assertion and reason are correct and relevant to each other.
• ii) Assertion is true but reason is not relevant to the assertion.
• 2. A process employed for the concentration of sulphide ore is __________. (froth floatation / gravity separation)
• 3. Coating the surface of iron with other metal prevents it from rusting. If it is coated with a thin layer of zinc, it is
• called _______ . (galvanization / painting / cathodic protection)
• 4. Any metal mixed with mercury is called an amalgam. The amalgam used for dental filling is _________.
• (Ag – Sn amalgam / Cu – Sn amalgam)
• 5. Assertion: In thermite welding, aluminium powder and Fe2O3 are used.
• Reason: Aluminium powder is a strong reducing agent. Does the reason satisfy the assertion?
• 6. Can the rusting of iron nails occur in distilled water? Justify your answer.
• 7. Iron reacts with con. HCl and con. H2SO4 , but it does not react with con.HNO3. Justify your answer with proper
• reasons.
• 8. To design the body of an aircraft, aluminium alloys are used. Give reasons.
• 9. X is a silvery white metal. X reacts with oxygen to form Y. The same compound is obtained from the metal on
• reaction with steam with the liberation of hydrogen gas. Identify X and Y.
• 10. Solve the crossword puzzle:
• 11. Give a single term for each of the following:
• i) The process of extracting ores from the earth’s crust.
• ii) The rocky impurities associated with the ores.
• iii) The substance added to the ore to reduce fusion temperature.
• iv) The process of reducing the roasted oxide ore to metal under molten condition.
• v) Noble metals occur in this state.
• 12. Connect the following metallurgical steps with the extraction of metals in the correct order:
• (roasting, bessemerisation, Hall’s process, smelting (reduction), Baeyer’s process, electrolytic refining, blast
• furnace, calcination, gravity separation, froth floatation process)
• Meta
• 13. Relate all the four columns of the table with unique properties:
• Metal Ore Chemical formula Reduction
• 14. Here are a few statements related to alloys. Identify the incorrect ones and correct them.
• i) It is a homogenous mixture of metals. ii) Zinc amalgam is used in dental filling.
• iii) Duralumin is used for making statues, coins, bells and gongs.
• iv) Alloys are produced by compressing finely divided metals one over the other. v) Zinc is the solvent of brass.
• 15. Complete the following table:
• Zone Temperature Chemical Process
• 16. Guess who I am?
• i) I am a cheap metal but highly reactive. Therefore, I sacrifice myself to save objects made of iron.
• ii) I am a solid solution. Dentists use me to fill cavities.
• iii) I am a constituent of blood pigment. When I am less in quantity, the person is anaemic.
• iv) I am formed when matrix and flux react.
• 17. Answer the following questions in one or two sentences:
• i) What is the percentage of gold present in ‘Hallmark’ gold?
• ii) What is the meaning of ‘chalcogens’?
• iii) What are the metals used in manufacture of science equipment?
• iv) Name the metal present in chlorophyll which is used in photosynthesis.
• v) When iron is exposed to moist air, a reddish brown substance is deposited on it. What is it? Give its composition.
• 18. Match the following:
• 13. Carbon and its Compound
• 1. Write down the possible isomers and give their IUPAC names using the formula C4H10.
• 2. Diamond is the hardest allotrope of Carbon. Give reason for its hardness.
• 3. An organic compound (A) is widely used as a preservative in pickle and has a molecular formula C2H4O2. This
• compound reacts with ethanol to form a sweet smelling compound (B).
• (i) Identify the compounds A and B. (ii) Name the process and write the corresponding chemical equation.
• 4. An organic compound (A) of molecular formula C2H6O on oxidation with alkaline KMnO4 solution gives an acid (B)
• with the same number of carbon atoms. Compound A is used as an antiseptic to sterilize wounds, in hospitals.
• Identify A and B. Write the chemical equation involved in the formation of B from A.
• 5. C2H6O is the molecular formula for two compounds A and B. They have different structural formula.
• i) What is this phenomenon known as?
• ii) Give the structural formula of A and B.
• iii) Write down their common and IUPAC names.
• iv) Mention the functional groups of A and B.
• 6. Rewrite the following choosing the correct word from each pair given in brackets:
• The hydrocarbons containing at least one carbon to carbon _______________ (double/ triple) bond are called
• __________(alkenes/alkynes).They have the general formula CnH2n..These were previously called
• ______________(olefins/paraffins). When this compound is treated with ____________(bromine/lime) water,
• decolourisation occurs because it is _____________(saturated/unsaturated).
• 7. Identify the compounds using the clues given below:
• i) This is a dark coloured syrupy liquid containing 30% of sucrose.
• ii) During manufacture of ethanol this is added as food for yeast.
• iii)This enzyme converts sucrose into glucose and fructose.
• iv) This compound contains 95.5% ethanol and 4.5% water.
• v) This compound contains 100% pure alcohol.
• 8. Read each description given below and say whether it fits for ethanol or ethanoic acid.
• i) It is a clear liquid with a burning taste.
• ii) It is used to preserve biological specimens in laboratories.
• iii) It is used to preserve food and fruit juices.
• iv) On cooling, it is frozen to form ice flakes which look like a glacier.
• 9. Match these words /sentences with appropriate statements given below:
• (methanol, fermentation, catenation, homologous series, hydrogen gas)
• i) The ability of carbon to form large number of compounds through self linking property.
• ii) Alcohols react with sodium to give this element.
• iii) This series helps in giving knowledge and enables systematic study of members.
• iv) Formation of simple molecules from complex organic compounds using enzymes.
• v) Unlike ethanol, the intake of this compound in very small quantities can cause death.
• 15. Law of Motion and Gravitation
• 1. Fill in the blanks.
• i) If force = mass x acceleration, then momentum = __________.
• ii) If liquid hydrogen is for rocket, then –––––––– is for MRI.
• 2. Correct the mistakes, if any, in the following statements.
• i) One newton is the force that produces an acceleration of 1 ms-2 in an object of 1 gram mass.
• ii) Action and reaction always act on the same body.
• 3. The important use of cryogenics is cryogenic fuels. What do you mean by cryogenic fuels?
• 4. As a matter of convention, an anticlockwise moment is taken as ________ and a clockwise moment is taken as ________.
• 5. A bullet of mass 20 g moving with a speed of 75 ms-1 hits a fixed wooden plank and comes to rest after penetrating
• a distance of 5 cm. What is the average resistive force exerted by the wooden plank on the bullet?
• 6. A shopping cart has a mass of 65 kg. In order to accelerate the cart by 0.3ms-2 what force would you exert on it?
• 7. Why does a spanner have a long handle?
• 8. Why does a boxer always move along the direction of the punch of the opponent?
• 9. The mats used in gyms and the padding used in sports uniforms are made up of soft substances. Why are rigid
• materials not used?
• 10. Write two principles that are used in rocket propulsion.
• 11. A 10 Kg mass is suspended from a beam 1.2 m long. The beam is fixed to a wall. Find the magnitude and direction
• (clockwise or anti-clockwise) of the resulting moment at point B.
• 12. If the force experienced by a body of unit mass is gravitational field strength, find the gravitational field strength
• on the surface of the earth.
• 13. If the density of the earth is doubled to that of its original value, the radius remaining the same, what will be the
• change in acceleration due to gravity?
• 14. Renu is standing in a dining line 6.38 x 103 km from the centre of the earth. The mass of the earth is 6 x 1024 kg.
• i) Find the acceleration due to gravity. ii) Will the value change after she finishes her lunch?
• 15. If an angel visits an asteroid called B 612 which has a radius of 20 m and mass of 104 kg, what will be the
• acceleration due to gravity in B 612 ?.
• 16. A man of mass ‘m’ standing on a plank of mass ‘M’ which is placed on a smooth horizontal surface, is initially at
• rest. The man suddenly starts running on the plank with a speed of ‘v’ m/s with respect to the ground. Find the
• speed of the plank with respect to the ground.
• 17. Two balls of masses in ratio 2:1 are dropped from the same height. Neglecting air resistance, find the ratio of
• i) the time taken for them to reach the ground.
• ii) the forces acting on them during motion.
• iii) their velocities when they strike the ground.
• iv) their acceleration when they strike the ground.
• 18. An object of mass 1 kg is dropped from a height of 20 m. It hits the ground and rebounds with the same speed.
• Find the change in momentum.(Take g=10 m/s2)
• 19. What will be the acceleration due to gravity on the surface of the moon, if its radius is 1/4th the radius of the earth
• and its mass is 1/80 times the mass of the earth.
• 20. A boy weighing 20 kg is sitting at one end of a see-saw at a distance of 1.2 m from the centre. Where should a man
• weighing 60 kg sit on the see-saw, so that it stands balanced?
• 21. A cart driver prods his horse to move forward. The horse refuses to budge and explains:
• “According to Newton’s III Law, I am pulling the cart, with a certain force and the cart, in turn pulls me back with an
• equal amount of force. As they are equal in magnitude and act in opposite directions, they cancel each other.” Do
• you agree with the explanation given by the horse? Support your answer with proper reasons.
• 16. Electricity and Energy
• 1. Fill in the blanks
• i) Potential difference : voltmeter; then current __________.
• ii) Hydro power plant : Conventional source of energy; then solar energy: _________.
• 2. In the list of sources of energy given below, find out the odd one.
• (wind energy, solar energy, hydro electric power)
• 3. Correct the mistakes, if any, in the following statements.
• i) A good source of energy would be one which would do a small amount of work per unit volume of mass.
• ii) Any source of energy we use to do work is consumed and can be used again.
• 4. The schematic diagram, in which different components of the circuit are represented by the symbols conveniently
• used, is called a circuit diagram. What do you mean by the term components?
• 5. The following graph was plotted between V and I values. What would be the values of V / I ratios when the
• potential difference is 0.5 V and 1 V?
• 6. We know that γ – rays are harmful radiations emitted by natural radio active substances.
• i) Which are other radiations from such substances?
• ii) Tabulate the following statements as applicable to each of the above radiations
• (They are electromagnetic radiation. They have high penetrating power. They are electrons. They contain neutrons)
• 7. Draw the schematic diagram of an electric circuit consisting of a battery of two cells of 1.5V each, three resistance of
• 5 ohm, 10 ohm and 15 ohm respectively and a plug key all connected in series.
• 8. Fuse wire is made up of an alloy of ___________ which has high resistance and _______.
• 9. Observe the circuit given and find the resistance across AB.
• 10. Complete the table choosing the right terms within the brackets.
• (zinc, copper, carbon, lead, lead dioxide, aluminium.)
• 11. How many electrons flow through an electric bulb every second, if the current that passes through the bulb is 1.6 A.
• 12. Vani’s hair dryer has a resistance of 50 Ω when it is first turned on.
• i) How much current does the hair dryer draw from the 230 V – line in Vani’s house?
• ii) What happens to the resistance of the hair dryer when it runs for a long time?
• (Hint : As the temperature increases the resistance of the metallic conductor increases.)
• 13. In the given network, find the equivalent resistance between A and B.
• 14. Old – fashioned serial lights were connected in a series across a 240V household line.
• i) If a string of these lights consists of 12 bulbs, what is the potential difference across each bulb?
• ii) If the bulbs were connected in parallel, what would be the potential difference across each bulb?
• 15. The figure is a part of a closed circuit. Find the currents i1, i2 and i3.
• 16. If the reading of the Ideal voltmeter (V) in the given circuit is 6V, then find the reading of the ammeter (A).
• 17. A wire of resistance 8 Ω is bent into a circle. Find the resistance across the diameter.
• 18. A wire is bent into a circle. The effective resistance across the diameter is 8 Ω. Find the resistance of the wire.
• 19. Two bulbs of 40 W and 60 W are connected in series to an external potential difference. Which bulb will glow
• brighter? Why?
• 20. Two bulbs of 70 W and 50 W are connected in parallel to an external potential difference. Which bulb will glow
• brighter? Why?
• 21. Write about ocean thermal energy?
• 22. In a hydroelectric power plant, more electrical power can be generated if water falls from a greater height. Give
• reasons.
• 23. What measures would you suggest to minimize environmental pollution caused by burning of fossil fuel?
• 24. What are the limitations in harnessing wind energy?
• 25. What is biomass? What can be done to obtain bioenergy using biomass?
• 26. Which form of energy leads to the least amount of environmental pollution in the process of harnessing and
• utilization? Justify your answer.
• 17. Magnetic Effect Of Electric Current And Light
• 1. Fill in the blanks
• i) For a motor : a permanent magnet, then commercial motor : _______
• ii) Focal length of a lens; metre, then for power of a lens____________
• 2. Correct the mistakes, if any, in the following statements.
• i) The magnetic field is a quantity that has magnitude only.
• ii) Outside the bar magnet, the magnetic field lines emerge from the south pole and merge at the north pole.
• 3. The ray diagram shown below is introduced to show how a concave mirror forms the image of an object.
• i) Identify the mistake and draw the correct ray diagram.
• ii) Write the justifications for your corrections.
• 4. In traffic signals _________ colour light is used to stop vehicles because it has ______ wave length. (Hint: scattering of
• light is inversely proportional to the fourth power of its wavelength)
• 5. Fill the table with the appropriate words given in bracket.
• ( Convex mirror, Plano convex, Concave mirror, Plane mirror, Convex lens, Concave lens)
• 6. Write down the names of the specified parts of the human eye.
• i) Dark muscular diaphragm that controls the pupil.
• ii) The screen where the image is formed by the eye lens.
• 7. You know that myopia is a common refractive defects of vision. A person with this defect can clearly see only objects
• that are near. Using concave lens of suitable power this defect is corrected.
• i) Mention the other two types of defects.
• ii) Explain how they can be corrected.
• 8. i) Which of the compass needle orientations in the following diagram correctly describes the magnet’s field at that
• point?
• 9. Does magnetic monopole exist? Give reasons.
• 10. A 3 cm tall bulb is placed at a distance of 20 cm from a diverging lens having a focal length of 10.5 cm. Determine
• the distance of the image.
• 11. A needle placed at 30 cm from the lens forms an image on a screen placed 60 cm on the other side of the lens.
• Identify the type of lens and determine the focal length.
• 12. A ray from medium 1 is refracted below while passing to medium 2. Find the refractive index of the second medium
• with respect to medium 1.
• 13. A real image, 1/5th the size of the object, is formed at a distance of 18 cm from a mirror. What is the nature of the
• mirror? Calculate its focal length.
• 14. A person cannot clearly see objects farther than 12 m from the eye. Name the defect in vision he is suffering from
• and the lens that should be used to correct this defect.
• 15. Explain the use of concave mirror as solar concentrators with the help of a ray diagram.
• 16. Light enters from air to kerosene having refractive index of 1.47. What is the speed of light in kerosene, if the speed
• of light in air is 3x108 m/s?
• 17. Murugan trims his beard while looking into a concave mirror whose focal length is 18 cm. He looks into it from a
• distance of 12 cm.
• i) How far is Murugan’s image from the mirror?
• ii) Does it matter whether or not Murugan’s face is closer or farther than the focal length? Explain.
• 18. Light travels at 1.90 x 108 m/s in a crystal, what is the crystal’s index of refraction?
• 19. Ranjini makes arrangements for a candle-light dinner and tops it with a dessert of gelatin filled blue berries. If a
• blueberry that appears at an angle of 450 to the normal in air is really located at 300 to the normal in gelatin, what
• is the index of refraction of the gelatin?
• 20. If the far point of a myopic person is 75 cm, what should be the focal length of the lens used to rectify this defect?
• 21. Reena and Vani find a discarded plastic lens lying on the beach. The girls discuss what they learnt in Physics and
• argue whether the lens is a converging or diverging one. When they look through the lens, they notice that the
• objects are inverted.
• i) If an object 25 cm in front of the lens forms an image 20 cm behind the lens, what is the focal length of the lens?
• ii) Is it a converging or diverging lens?
• 22. Light which is incident on a flat surface makes an angle of 150 with the surface.
• i) What is the angle of incidence?
• ii) What is the angle of reflection?
• iii) Find the angle of deviation.
• 23. How can you identify the three types of mirrors without touching them? Give reasons.
• 24. What will happen when the frequency of rotation in an AC dynamo is doubled?