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 AssessmentII, 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.

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SUMMATIVE ASSESSMENT II, 2012 II, 2012SCIENCE /

67041

Class X /Time allowed : 3 hours 3 General Instructions :(i) (ii) (iii) (iv) (v) (vi) (vii) (viii) (ix)

XMaximum Marks : 80 80

The question paper comprises of two Sections, A and B. You are to attempt both the sections. All questions are compulsory. 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. All questions of Section-A and all questions of Section-B are to be attempted separately. Question numbers 1 to 4 in Section-A are one mark questions. These are to be answered in one word or in one sentence. Question numbers 5 to 13 in Section-A are two marks questions. These are to be answered in about 30 words each. Question numbers 14 to 22 in Section-A are three marks questions. These are to be answered in about 50 words each. Question numbers 23 to 25 in Section-A are five marks questions. These are to be answered in about 70 words each. 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) (vi) (vii) (viii) (ix) 1 5 14 23 26 4 13 22 25 41 30 50 70

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SECTION-A / 1. What is common name of CH3COOH ? CH3COOH 2. Why are the danger signals on the cross roads red in colour ?

3.

Pick the biodegradable substances from the following : Cotton, rubber, leather, radioactive material.

4.

Select the Abiotic components of the environment from the following :Light, fungus, monkey, humidity.

5.

(a) (b) (a) (b)

An element has electronic configuration 2, 8, 6. Explain its position in the periodic table. Size of sodium atom is bigger than that of hydrogen atom. Why ? 2, 8, 6

6.

(a) (b) (a) (b)

State modern periodic law. What is the similarity in the valency of all the elements of group 1 in the modern periodic table ?

7.

What is meant by DNA copying? Mention its importance in reproduction? DNA

8.

Write two advantages of vegetative propagation?

9.

Define power of a lens. Find power of a concave lens of focal length 2 m. 2m

10.

A student sitting in the last row cannot read clearly the letters written on the blackboard. What could be the defect of vision the student is suffering from ? Suggest the type of lens to correct his vision. Page 3 of 13

11.

List two reasons to explain the twinkling of stars.

12.

How are fossil fuels formed ? Why should we use these resources judiciously ? ? ? It is said that participation of the local people can indeed lead to the efficient management of forests. To what extent this holds true ? Explain briefly with the help of an example. ``` ` ?

13.

14.

(a) (b) (a) (b)

Draw a diagram to illustrate formation of triple bond between two atoms of Nitrogen. (Atomic number of Nitrogen is 7) Out of two compounds ethane and ethene, which is more reactive ? Give reason for your answer. 7

15.

Group 15 Group 16 A C D B E Giving reasons, explain the following : (a) Element A is a non metal. (b) Element D is more electronegative than E. (c) Which type of ion, cation or anion will be formed by element C ? 15 16 A B (a) (b) (c) A D C E C D E

16.

Draw the labelled diagram of female reproductive system. Name the organ which provides nutrition to embryo? Where is it located?

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17.

How is the sex of a newborn determined genetically in human beings ? Explain with the help of a suitable diagram.

18.

The traits acquired during the lifetime of an individual are not inherited. Give reason and justify this statement giving two examples.

19.

Define the terms (i) Natural Selection and (ii) Genetic Drift. How do they change the frequency of certain genes over generations in a population ? (i) (ii)

20.

An object of height 5 cm is placed at a distance of 25 cm from a concave mirror of radius of curvature 30 cm. Calculate the distance and the size of the image formed by the mirror. 5 cm 30 cm 25 cm

21.

A lens has power 2D. Find the focal length and nature of this lens. An object is placed at a distance of 100 cm from this lens. Where will the image be formed and what will be its nature ? 2D 100 cm

22.

What is meant by the power of accommodation of human eye ? When do we consider a person to be hypermetropic ? Draw a ray diagram to show how hypermetropia is corrected using a suitable lens.

23.

(a)

Complete the following equation4 CH3CH2 OH

Alkaline KMnO Heat

(b)

(c) (a)

What is the role of alkaline KMnO4 in the above chemical change ? Name the following compounds : (i) CH3CH2CH2CH3 (ii) CH3 COCH3 Name and define the property due to which carbon is able to form bonds with other carbon atoms. Page 5 of 13

4 CH3CH2 OH

KMnO

KMnO4 (b) (i) (ii) (c) OR/ (a) (b) (c) (a) (b) (c) What happens when a piece of sodium metal is dropped in ethanol ? Write the chemical reaction involved. Sometime bottoms of cooking vessels get blackened while cooking food When and why does it so happen ? Differentiate between saturated and unsaturated hydrocarbons. (2 points) CH3CH2CH2CH3 CH3 COCH3

24.

(a) (b)

Draw a labelled diagram of longitudinal section of flower Name the male and female reproductive part in a bi-sexual flower. Explain function of each in brief .

(a) (b) OR/ (a) (b) (a) (b) 25. Explain with the help of suitable diagram the following terms in connection with spherical lenses (i) (iv) Centre of curvature Optical centre (ii) (v) Principal axis Aperture (iii) Principal focus Draw a labelled diagram of germination of pollen on stigma Explain the process of germination.

(i)

(ii)

(iii)

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(iv)

(v) OR/

An extended object is placed perpendicular to the principal axis of a convex lens. Draw neat diagrams to show the image formation in the following cases (a) (b) (c) The object is between 2f and infinity. The object is at 2f. The object is between f and 2f.

(a) (b) (c)

2f 2f f 2f SECTION - B /

26.

A strip of copper was placed in a beaker containing zinc sulphate solution. On observing the strip next day, it was noticed that : (a) the copper strip remained as it was (b) the copper strip became thinner (c) the copper strip became thicker (d) the colour of the strip changed

(a) (b) (c) (d) 27. Zinc granules were added to ZnSO4, CuSO4 Al2 (SO4)3 and FeSO4 solutions as shown below. After about one hour a deposition of metal on the zinc granules will be observed in beakers.

(a) (c)

I and III I and II

(b) II and IV (d) III and IV ZnSO4, CuSO4 Al2 (SO4)3

FeSO4

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(a) (c) 28.

I I

III II

(b) (d)

II III

IV IV

Four students recorded the odour of Ethanoic acid as given below. Student Observation A Similar to vinegar B Similar to Lemon juice C Similar to nail polish remover D Similar to Petrol Whose observation is correct ? (a) A (b) B (c)

C

(d)

D

A B C D (a) 29. A (b) B (c) C (d) D

While studying the properties of acetic acid you would observe that acetic acid : (a) Produces CO2 gas on reacting with sodium hydroxide solution. (b) (c) (d) (a) (b) (c) (d) produces hydrogen on reacting with sodium hydrogen carbonate. turns red litmus blue. turns blue litmus red. CO2

30.

When a pinch of Sodium bicarbonate is added to a test tube containing Ethanoic acid, which of the following things would happen : (a) Vigorous evolution of a gas (b) A white precipitate is formed (c) Sodium bicarbonate simply dissolves in Ethanoic acid with no evolution of a gas (d) A gas with foul odour is evolved. Page 8 of 13

(a) (b) (c) (d) 31. The focal length of the concave mirror in the experimental set up, shown below equals :

(a)

10.3cm

(b)

11.0cm

(c)

11.7 cm

(d)

12.2cm

ZrMo Xem`r J`r mmo{JH$ dWm | AdVb XnU H$s $moH$g Xar h-

(a) 32.

10.3cm

(b)

11.0cm

(c)

11.7 cm

(d)

12.2cm

Four students A, B, C and D carried out measurement of focal length of a concave mirror as shown in the following four diagrams.

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The best result will be obtained by student (a) A (b) B (c)A, B, C, D

C

(d)

D

(a)33.

A

(b)

B

(c)

C

(d)

D

Out of the following objects which one would you prefer to determine the focal length of a Page 10 of 13

given convex lens by focusing its image or a screen ? (a) A burning candle placed on the far end of a laboratory table (b) Grills of the laboratory window (c) A tall tree visible from the laboratory window (d) Sun rays entering the laboratory through its window.

(a) (b) (c) (d) 34. Four students traced the path of a ray of light passing through a glass slab. The correct trace is that of student.

(a)

I

(b)

II

(c)

III

(d)

IV

(a) 35.

I

(b)

II

(c)

III

(d)

IV

On the basis of experiments performed by students with rectangular glass slabs the correct interpretation about the incident ray, refracted ray and the emergent ray would be(a) i >e (b) ee e