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Important Instructions for the

School Principal

(Not to be printed with the question paper)

1) This question paper is strictly meant for the use in School Based Summative Assessment-

II, March-2012 only. This question paper is not to be used for any other purpose except

mentioned above under any circumstances.

2) The intellectual material contained in the question paper is the exclusive property of

Central Board of Secondary Education and no one including the user school is allowed to

publish, print or convey (by any means) to any person not authorised by the Board in this

regard.

3) The School Principal is responsible for the safe custody of the question paper or any other

material sent by the Central Board of Secondary Education in connection with School

based SA-II, March-2012, in any form including the print-outs, compact-disc or any other

electronic form.

4) Any violation of the terms and conditions mentioned above may result in the action

criminal or civil under the applicable laws/byelaws against the offenders/defaulters.

Note: Please ensure that these instructions are not printed with the question

paper being administered to the examinees.

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SUMMATIVE ASSESSMENT – II, 2012

II, 2012

SCIENCE /

Class – X / X

Time allowed : 3 hours Maximum Marks : 80

3 80

General Instructions :

(i) The question paper comprises of two Sections, A and B. You are to attempt both the

sections.

(ii) All questions are compulsory.

(iii) There is no overall choice. However, internal choice has been provided in all the five

questions of five marks category. Only one option in such questions is to be attempted.

(iv) All questions of Section-A and all questions of Section-B are to be attempted separately.

(v) Question numbers 1 to 4 in Section-A are one mark questions. These are to be answered in

one word or in one sentence.

(vi) Question numbers 5 to 13 in Section-A are two marks questions. These are to be answered

in about 30 words each.

(vii) Question numbers 14 to 22 in Section-A are three marks questions. These are to be

answered in about 50 words each.

(viii) Question numbers 23 to 25 in Section-A are five marks questions. These are to be answered

in about 70 words each.

(ix) Question numbers 26 to 41 in Section-B are multiple choice questions based on practical

skills. Each question is a one mark question. You are to select one most appropriate

response out of the four provided to you.

(i)

(ii)

(iii)

(iv)

(v) 1 4

(vi) 5 13 30

(vii) 14 22 50

(viii) 23 25 70

(ix) 26 41

SC - 2021

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SECTION – A /

1. Name a functional group present in (i) CH3CHO; (ii) C2H5COOH

(i) CH3CHO; (ii) C2H5COOH

2. Name the condition resulting due to the eye lens becoming cloudy.

3. Choose any two biodegradable wastes from the following .

Cowdung, DDT, plastic, radioactive waste, vegetable peel

4. What happens during the first step of ozone formation in the atmosphere ?

5. State modern periodic law. What are vertical columns and horizontal rows in a periodic table

known as ?

6. (a) How does the tendency to gain electrons change as we go down a group ? Give reason.

(b) Given below is a part of the periodic table. How does the valency vary, as we move vertically downward from Li to Fr. Give reason.

Li Be

Na

K

Rb

Cs

Fr Ra

(a)

(b) Li Fr

Li Be

Na

K

Rb

Cs

Fr Ra

7. Draw a diagram to show the germination of pollen on stigma and label the following parts.

(i) Ovary (ii) pollen tube

(i) (ii)

8. How can pregnancy be prevented surgically ?

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9. What is meant by power of a lens ? Give its S.I. unit. When two or more lenses are placed in contact what will be their combined power ?

S.I

10. What is a rainbow ? When and how is it formed ?

11. Explain the cause of the red colour of the Sun at Sunrise and Sunset.

12. List four advantages of water stored in the ground.

13. “We need to use fossil fuels judiciously.” Justify this statement

14. A neutral organic compound A of molecular formula C2H6O on heating with excess of

conc.H2SO4 gives compound B of molecular formula C2H4. Compound B on reduction gives compound C of molecular formula C2H6. (a) Name A,B and C (b) Write chemical equation for the conversion of A to B. (c) What is the role of conc. H2SO4 in the above equation.

A C2H6O H2SO4 C2H4

B B C2H6 C

(a) A, B C

(b) A B

(c) H2SO4

15. The electronic configuration of three elements X, Y and Z are given below.

X 2 Y 2, 6 Z 2, 8, 2 (i) Which element belongs to the second period ? (ii) Which element belongs to the eighteenth period ? (iii) Which element belongs to the second group? (iv) What is the valency of Y ? (v) Y and Z, are they metal or a non – metal ?

X, Y Z

X 2 Y 2, 6 Z 2, 8, 2

(i)

(ii)

(iii)

(iv) Y

(v) Y Z,

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16. Mention one example each of viral and bacterial infections affecting the human reproductive system. What are such diseases called ? How can they be prevented ? Mention one more function of the above method used.

17. With the help of a cross done with garden pea plants, trace the work done by Mendel with a tall

and a short plant to arrive at a 3: 1 ratio in the F2 generation.

F2 3 : 1

18. Forelimbs of man and frog are they homologous or analogous organs ? Give reason for your

choice. How does it help in the study of evolution ?

19. (a) What are fossils ? How are they formed ?

(b) In which layer of the earth will we find fossils of organisms that lived in the recent past ?

20. An image 2/3rd the size of the object is formed by a concave mirror at a distance of 20 cm from

it. Find the focal length of the mirror.

2/3 20 cm

21. Draw and describe the image formed by a convex lens when the object is kept at (a) it focus F (b) between F and 2 F.

(a) F (b) F 2 F

22. List two causes leading to myopia of the eye. Draw ray diagrams to show the image formation in case of defective eye and corrected eye.

23. (a) How would you name the following compounds ? (i) CH3-CH2-CH=CH2 (ii) CH3-CH2-CH2-C(CH3)-CH3

(iii) CH3-CH2-CHO (iv) CH3-CH(OH)-CH3 (b) List four characteristic of homologous series. (c) Draw the electron dot structure of carbon –di- oxide

(a)

(i) CH3-CH2-CH=CH2 (ii) CH3-CH2-CH2-C(CH3)-CH3

(iii) CH3-CH2-CHO (iv) CH3-CH(OH)-CH3

(b)

(c)

OR/

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(a) Complete the following chemical equation and name the product.

(i) Na + CH3 – CH2 – OH

(ii) CH3COOH + CH

3CH

2OH H

(b) Write the chemical equation used in the preparation of soap ? Name the reaction. (c) What are detergents ? How are detergents better than soap ?

(a)

(i) Na + CH3 – CH

2 – OH

(ii) CH3COOH + CH

3CH

2OH H

(b)

(c)

24.

(a) Identify the organisms and the mode of asexual reproduction exhibited by them. (b) How will an organism be benefited if it reproduces through spores ? (c) Mention the two asexual methods by which hydra can reproduce. Explain briefly any

one such method.

(a)

(b)

(c)

OR/

(a) Name the parts 1, 2, 3, 4 . Shown in the diagram (b) Mention two functions of part 4. (c) Where does fertilization happen in this reproductive system ? (d) Why does the lining of uterus become thick and spongy every month?

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(a) 1, 2, 3 4

(b) 4

(c)

(d)

25. (a) State Snell‟s law of refraction.

(b) When a ray of light travelling in air enters obliquely into a glass slab, it is observed that the light ray emerges parallel to the incident ray but it is shifted side ways slightly. Draw a ray diagram to illustrate it.

(c) The refractive index of Benzene is 3/2 and that of Sapphire is 7/4. What is the refractive index of Sapphire when a ray of light enters Sapphire from Benzene.

(a)

(b)

(c) 3/2 7/4

OR/

(a) Differentiate a real image from a virtual image giving two points of difference. (b) Give two widely used applications of a convex mirror. (c) An object is placed at a distance of 20 cm from a convex mirror of focal length 15 cm. Find the position and nature of the image.

(a)

(b)

(c) 15 cm 20 cm

SECTION – B /

26. 10 mL of freshly prepared FeSO

4 was taken in each of four test tubes. Strips of Cu, Zn, Al and

Fe were introduced in different test tubes. Metal deposition was obtained in two of them. The right pair of metals forming the precipitate is : (a) Cu and Zn (b) Al and Cu (c) Fe and Al (d) Zn and Al

FeSO4

10 mL Cu, Zn, Al

Fe

(a) Cu Zn (b) Al Cu (c) Fe Al (d) Zn Al

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27. To show that Zn is more reactive than Fe, the correct procedure is to : (a) Prepare FeSO4 solution and dip Zn granule in it. (b) Prepare ZnSO4 solution and dip Fe nails in it . (c) mix ZnSO4 salt and FeSO4 salt in powdered form. (d) Mix aqueous solutions of FeSO4 and ZnSO4

Fe Zn

(a) FeSO4 Zn

(b) ZnSO4 Fe

(c) ZnSO4 FeSO4

(d) FeSO4 ZnSO4

28. An aqueous solution of acetic acid :

(a) turns wet blue litmus paper red (b) turns dry blue litmus paper red (c) turns both dry and wet blue litmus paper red (d) will not turn both dry and wet blue litmus paper wet.

(a)

(b)

(c)

(d)

29. When you open the cork of a bottle containing acetic acid, you observe a smell like :

(a) a lemon (b) an orange (c) burning sulphur (d) vinegar

(a) (b)

(c) (d)

30. On adding sodium hydrogen carbonate to acetic acid in a test tube, a gas is evolved which

turns lime water milky. It is due to the formation of : (a) calcium acetate (b) calcium carbonate (b) calcium hydroxide (d) calcium bicarbonate

(a) (b)

(c) (d)

31. A student has to perform an experiment on finding the focal length of a convex lens by distant

object method. The experiment can be performed if she has with her : (a) a lamp, a scale and a screen. (b) only a screen. (c) a scale and a screen. (d) a scale only.

(a) (b)

(c) (d)

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32. For finding the focal length of a concave mirror by obtaining the image of a distant object,

which one of the following would you like to focus ?

(a) flame of a candle kept at the other end of the table

(b) any distant tree

(c) window grill of the laboratory

(d) a well lit distant tower.

(a)

(b)

(c)

(d)

33. A student obtained a sharp image of a distant building on the screen placed behind a convex

lens. He then removed the screen and tried to look through the lens in the direction of the

building. He would now observe :

(a) an erect image of the building on the lens.

(b) an inverted image of the building at the focus of the lens.

(c) no image as the screen has been removed.

(d) a blurred image on the wall of the laboratory .

(a)

(b)

(c)

(d)

34. A student traces the path of a ray of light through a rectangular glass slab for angles of incidence 40 , 50 , 60 separately. He observed that the perpendicular distance „l‟ between the incident ray and emergent ray :

(a) increased with increase in angle of incidence. (b) decreased with increase in angle of incidence. (c) remained the same for all the three angles. (d) increased and then decreased

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40, 50 60

„l‟ :

(a)

(b)

(c)

(d)

35. A student who traced a path of ray through a glass slab, measured the angles of incidence,

refraction and emergence as shown in the figure. His measurement would be correct if he finds :

(a) i < r, i e (b) r < i, i e

(c) i e r (d) i e, i > r

(a) i < r, i e (b) r < i, i e

(c) i e r (d) i e, i > r

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36. Which stage out of those marked (i) (ii) (iii) and (iv) is shown binary fission in amoeba ?

(a) (i) (b) (ii) (c) (iii) (d) (iv)

(i), (ii), (iii) (iv)

(a) (i) (b) (ii) (c) (iii) (d) (iv)

37. The following figures illustrate asexual reproduction in amoeba in an incorrect sequence.

The correct sequence is :

(a) (i), (iii), (iv), (ii) (b) (ii), (iii), (iv), (i)

(c) (iv), (iii), (ii), (i) (d) (iii), (iv), (ii), (i)

(a) (i), (iii), (iv), (ii) (b) (ii), (iii), (iv), (i)

(c) (iv), (iii), (ii), (i) (d) (iii), (iv), (ii), (i)

38. Two of the following four figures that illustrate budding are :

(a) i and ii (b) i and iii (c) i and iv (d) ii and iv

(a) i ii (b) i iii (c) i iv (d) ii iv

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39. In the slides showing binary fission in amoeba and budding in yeast, the correct observations are : (a) the daughter cells of amoeba and bud in yeast are smaller than their respective parental

cells (b) the daughter cells of amoeba and the bud of yeast are of the same size as their respective

parental cells. (c) the daughter cells of amoeba are bigger than the parent cell but the bud of yeast is

smaller than the part (d) the daughter cells of amoeba are smaller than the parent but bud of yeast is larger than

parent.

(a)

(b)

(c)

(d)

40. While determining the percentage of water absorbed by raisins it is suggest that the wet raisins

should be wiped off gently before final weighing with the help of (a) a cotton cloth (b) a silken cloth (c) a filter paper (d) cotton wool

(a) (b)

(c) (d)

41. Some dry raisins weighed 5g before they were placed in water at room temperature for about

2 hours. The raisins were then removed, wiped and weighed again. Their weight was now found to be 6.25g. The percentage of water absorbed by raisins is : (a) 25% (b) 20% (c) 12.5% (d) 10%

5 g

2 6.25 g

(a) 25% (b) 20% (c) 12.5% (d) 10%

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