2011 SA 1 Science

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SUMMATIVE ASSESSMENT - I (2011)

Lakdfyr ijh{kk&I (2011)

SCIENCE / foKku Class X / & X

Time allowed : 3 hours Maximum Marks : 80 fu/kkZfjr le; % 3 ?k.Vs vf/kdre vad % 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 to section A and all questions of section B are to be attempted separately. v). Questions 1 to 4 in section A are one mark questions. These are to be answered in one word or

one sentence. vi). Questions 5 to 13 in section A are two marks questions. These are to be answered in about 30

words each. vii). Questions 14 to 22 in section A are three marks questions. These are to be answered in about 50

words each. viii). Questions 23 to 25 in section A are five marks questions. These are to be answered in about 70

words each. ix). Questions 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.

lkekU; funsZk %

(i) bl izu i= dks nks Hkkxksa, Hkkx v vkSj Hkkx c esa ckaVk x;k gSA vkidks nksuksa Hkkxksa ds izuksa ds mRrj fy[kus gSaA

(ii) lHkh izu vfuok;Z gSaA

(iii) iwjs izu i= ij dksbZ p;u izkIr ugha gS ijUrq ikap&ikap vadks ds ikWap izuksa esa Hkhrjh p;u fn;k x;k gSA bu izuksa esa vki dsoy ,d Hkhrjh p;u dks mRrj fy[kus ds fy, pqu ldrs gSaA

(iv) vkidks Hkkx v vkSj Hkkx c ds lHkh izuksa ds mRrj i`Fkd&i`Fkd fy[kus gksaxsA

(v) Hkkx v ds izu la[;k 1 ls 4 ds izu ,d&,d vad ds gSaaA buds mRrj ,d kCn vFkok ,d okD; esa nsaA

(vi) Hkkx v ds izu la[;k 5 ls 13 ds izu nks&nks vadksa ds gSaA buds mRrj yxHkx 30&30 kCnksa esa nsus gSaA

(vii) Hkkx v ds izu la[;k 14 ls 22 ds izu rhu&rhu vadksa ds gSaA buds mRrj yxHkx 50&50 kCnksa esa nsus gSaA

(viii) Hkkx v ds izu la[;k 23 ls 25 ds izu ikap&ikap vadksa ds gSaA buds mRrj yxHkx 70 kCnksa esa nsus gSaA (ix) Hkkx c ds izu la[;k 26 ls 41 ds izu iz;ksxkRed dkSky ij vk/kkfjr cgqfodYih izu gSaA izR;sd izu ,d vad dk gSA

fn, x;s pkj fodYiksa esa ls vkidks dsoy ,d lcls mi;qDr fodYi pquuk gSA

SECTION-A / ' '

1. Explain the term rancidity.

570037

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2. An element A forms two oxides AO and AO2. The oxide AO is neutral whereas the oxide

AO2 is acidic in nature. Would you call element A a metal or a non-metal ?

AO AO2 AO AO2

A

3. State the property of black surface which is used in the working of solar heaters.

4. State the relationship between 1 volt and 1 joule.

5. What are the products formed when magnesium metal reacts with water ? Why do the

pieces of metal start floating during the reaction ?

6. It is advised to pour acid into water rather than water to acid for the dilution of acids. Why ?

7. What is meant by a skeletal chemical equation ? Using suitable chemical reaction,

differentiate between a skeletal chemical equation and balanced chemical equation.

8. When a green iron compound is heated strongly, its colour changes to black and odour of

burning sulphure is given out.

(a) Name the compound

(b) State the type of reaction

(c) Write the chemical equation involved

(a)

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(b)

(c)

9. Mention the two main components of the transport system in plants. State one function of

each one of these components.

10. Large scale use of nuclear energy becomes prohibitive due to some hazards. State

any two major hazards associated with a nuclear power plant.

11. Aluminium wire has radius 0.25 mm and length of 75 m. If the resistance of the wire is

10 , calculate the resistivity of aluminium.

0.25 mm 75 mm 10

12. A student performs an experiment to study the magnetic effect of current around a current

carrying straight conductor with the help of a magnetic compass. He reports that

(i) the degree of deflection of the magnetic compass increases when the compass is moved

away from the conductor.

(ii) the degree of deflection of the magnetic compass increases when the current

through the conductor is increased.

Which of the above observations of the student appears to be wrong and why ?

(i)

(ii)

13. How would the reading of (V) change if it is connected between B and C ? Justify your

answer.

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(V) B C

14. State what is observed when water is added slowly to a small amount of calcium oxide (quick lime). Name the type of reaction that takes place and write a balanced chemical equation for the reaction involved.

15. The products obtained on electrolysis of concentrated aqueous solution of a substance X are

NaOH, Cl2 and H2.

(a) Name the substance X.

(b) What is the special name of this process and why ?

(c) Which gas is liberated at anode ?

(d) List one commercial use of NaOH.

X NaOH, Cl2 H2

(a) X

(b)

(c)

(d) NaOH

16. (a) Equal lengths of Mg ribbon 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. In which case the reaction

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would occur more vigorously and why ? Write the chemical equations for reactions in

test tube A and B.

(b) Fresh milk has a pH of 6. How will the pH change as it turns into curd ? Give reason

for your answer.

(a) A B A

B

A B

(b) pH 6 pH

17. (a) Which hormone is responsible for the changes noticed in males at puberty ?

(b) Deficiency of which hormone leads to dwarfism.

(c) Name the hormone which is injected to a diabetic patient.

(a)

(b)

(c)

18. (a) Which hormone is secreted when growing plants detect light?

(b) How does this hormone help the shoot to bend towards light ?

(a)

(b)

19. What are the factors that should be taken into consideration for selecting a source of energy ?

List any three.

20. A piece of wire of resistance 20 is drawn out so that its length increases to twice its original

length. Calculate the resistance of the wire in the new situation.

20

21. (a) What is the total resistance of n resistors each of resistance R connected in :

(i) Series (ii) Parallel ?

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(b) Calculate the resultant resistance of 3 resistors 3 , 4 and 12 connected in parallel.

(a) R n (i) (ii)

(b) 3 , 4 12

22.

(i) What precautions should be taken to avoid the overloading of domestic electric circuits ?

(ii) An electric oven of 2 kW power rating is operated in a domestic electric circuit of that has a current rating 5A. If the supply voltage is 220V, what result do you expect? Explain.

(i)

(ii) 2 kW 220V

5A

23. (a) Write the electron dot structure for calcium and oxygen. The atomic numbers of

calcium and oxygen are 20 and 8 respectively.

(b) Show the formation of calcium oxide by the transfer of electrons.

(c) Give reason for the following:

(i) Ionic compounds are hard solids

(ii) Ionic compounds conduct electricity in the molten state but not in the solid state.

(a)

20 8

(b)

(c)

(i)

(ii)

OR Describe in brief an activity to investigate the conditions under which an article made of iron

rusts. List any four methods used for the prevention of rusting of iron.

24. (i) Leaves of a healthy potted plant were coated with vaseline to block the stomata. Will

this plant remain healthy for long ? State three reasons for your answer.

(ii) State any two differences between autotrophic nutrition and hetrotrophic nutrition.

(i)

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(ii)

OR (A) Draw a sectional view of the human heart and label on it the following parts :

(i) Aorta (ii) Pulmonary arteries

(iii) Vena cava from upper body (iv) Left ventricle

(B) Why is double circulation of blood necessary in human beings ?

(A)

(i) (ii)

(iii) (iv)

(B)

25. (a) Name the scientist who discovered that a moving magnet can be used to generate

electric current. With which name is this phenomenon known ?

(b) Two coils 1 and 2 of insulated copper wire having large but different number of turns

are wound over a cardboard cylinder. Coil 1 is connected to battery and a plug key.

Coil 2 is connected to a galvanometer. How will the galvanometer reading change

when ?

(i) key is plugged in and

(ii) key is taken out.

Give reason for your answer.

(c) Name and state the rule used for determination of direction of induced current due to a

changing magnetic field and give one practical application of this phenomenon in

everyday life.

(a)

(b) 1 2

1

2

(i)

(ii)

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(c)

OR (a) Consider a circular loop of wire lying in the plane of the paper. Let the current pass

through the loop clockwise. With the help of a diagram explain how the direction of

the magnetic field can be determined inside and outside the loop. Name the law used

to find the direction of magnetic field.

(b) Draw a diagram to represent a uniform magnetic field in a given region.

(c) List two properties of magnetic field lines.

(a)

(b)

(c)

SECTION B / ' '

26. A student was observing a pH chart. He observed that the two colours at the extreme ends

of the pH chart are :

(a) red and green (b) red and blue

(c) green and blue (d) orange and green

pH pH

(a) (b)

(c) (d)

27. The pH value of a solution is 6. What is the colour developed when a student adds 3

drops of universal indicator in the solution

(a) Red (b) Blue (c) Green (d) Orange

pH 6

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(a) (b) (c) (d)

28. Four students performed the reactions of dil Hydrochloric acid and a solution of sodium

hydroxide with zinc metal and solid sodium carbonate separately. They reported the

possible reaction by () and no reaction by (X). In which of the following sets all

observations are correct ?

() ()

29. When iron nail is kept in copper sulphate solution for about 3-4 hours, it is observed that

(a) only the tip of nail get the coating of copper

(b) only the bottom of the nail get the coating of copper

(c) whole nail get the coating of copper

(d) no coating is formed on the nail

3 - 4

(a)

(b)

(c)

(d)

30. When aqueous solutions of sodium sulphate and barium chloride are mixed together we find

Set HCl + Zn HCl + Na2CO3 NaOH + Zn NaOH + Na2 CO3

(a)

(b)

(c)

(d)

Set HCl + Zn HCl + Na2CO3 NaOH + Zn NaOH + Na2 CO3

(a)

(b)

(c)

(d)

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that the reaction mixture :

(a) turns red (b) forms a white precipitate

(c) forms a yellow precipitate (d) remains colourless

(a) (b)

(c) (d)

31. In an experiment a student is using following measuring instruments having 50

division each on their scales

Ammeter (0-5A)

Voltmeter (0-10V)

The respective least count of these instruments are

(a) 0.2A ; 0.2V (b) 0.1A ; 0.1V

(c) 0.2A ; 0.1V (d) 0.1A ; 0.2V

50

(0-5A)

(0-10V)

(a) 0.2A ; 0.2V (b) 0.1A ; 0.1V

(c) 0.2A ; 0.1V (d) 0.1A ; 0.2V

32. A student draws the circuit diagram as shown. The parts labelled X, Y and Z respectively

are :

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(a) Ammeter, resistor, voltmeter

(b) Ammeter, voltmeter, resistor

(c) Voltmeter, resistor, ammeter

(d) Voltmeter, ammeter, resistor

X, Y Z

(a)

(b)

(c)

(d)

33. The following circuit diagram shows the experimental set up for the study of dependence of

current on potential difference. Which two circuit components are connected in series.

(a) battery and voltmeter (d) ammeter and voltmeter

(c) ammeter and rheostat (d) resistor and voltmeter

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(a) (b)

(c) s (d)

34. To determine the equivalent resistance of two resistors in parallel combination a circuit

is shown below. The component of the circuit whose terminals are wrongly connected

is :

(a) rheostat (b) cell (c) volt meter (d) ammeter

(a) (b) (c) (d)

35. Two resistances R1 and R2 are to be connected in series combination. Out of the

following the correct combination is shown in :

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(a) only A (b) only B

(c) only C (d) all of them A, B and C

R1 R2

(a) A (b) B

(c) C (d) A, B C

36.

Steps involved to test the presence of starch in a leaf are shown by figure (i), (ii), (iii) and (iv)

which are not in correct sequence ? Which one of the following is the correct sequence for the

process to test the starch ?

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

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

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

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

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

37. A destarched leaf of a potted plant is partially covered with black strip of paper on the upper

and lower surfaces as shown in the figure and kept in sunlight. The starch test was

performed after this. What will be the colour of the regions marked as A and B in the leaf ?

(a) A-blue black, B-pale (b) A-green, B-pale

(c) A-pale, B-blue black (d) A-blue black, B-green

A B

(a) A - B - (b) A - B -

(c) A - B - (d) A - B -

38. Temporary mount of a peel is made in :

(a) Alcohol (b) Water

(c) Glycerine (d) Acetone

(a) (b)

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(c) (d)

39. Coverslip is put on the slide very gently to avoid :

(a) Entry of air bubbles (b) Crushing of the material

(c) Oozing of glycerine (d) None of these

(a) (b)

(c) (d)

40. Observe the following set up and choose the right reason as to why water has not risen in the

delivery tube.

(a) The set up is airtight.

(b) Beaker has coloured water.

(c) CO2 is not being absorbed

(d) O2 is not available to seeds for respiration

(a)

(b)

(c) CO2

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(d) O2

41. The correct set of three precautions for setting up the experiment to demonstrate that

CO2 is evolved during respiration is :

(a) Thread holding KOH test tube, Airtight flask, delivery tube above water surface

in the beaker

(b) Flask has just germinated seeds, Airtight set up, delivery tube dip in water in

beaker.

(c) Flask has seeds covered with water, Airtight set up, KOH test tube held by a thick

wire.

(d) Just germinated seeds under water in the flask, delivery tube above water level, Thread

holding KOH test tube.

CO2

(a) KOH

(b)

(c) KOH

(d) KOH

Documents

2011 SA 1 Science