delhi public school tapi · (ix) question numbers 25to 36in section-bare practical based questions...
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DELHI PUBLIC SCHOOL TAPI CLASS X
SUMMATIVE ASSESSMENT 1
SUBJECT: GEN. SCIENCE
CODE: 086
DATE: 30/09/14 TOTAL MARKS: 90
DURATION: Reading – 15 Mins. + Writing – 2 Hr. 45 Mins. + Revision – 15 Mins.
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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. (iv) All questions of Section-A and all questions of Section-B are to be attempted
separately. (v) Question numbers 1 to 3 in Section-A are one mark questions. These are to be
answered in one word or in one sentence. (vi) Question numbers 4 to 6 in Section-A are two marks questions. These are to be
answered in about 30 words each. (vii) Question numbers 7 to 18 in Section-A are three marks questions. These are to be
answered in about 50 words each. (viii) Question numbers 19 to 24 in Section-A are five marks questions. These are to be
answered in about 70 words each. (ix) Question numbers 25 to 36 in Section-B are practical based questions (PBQs). Question
numbers 25 to 33 are MCQs carrying one mark each. You are to choose one most appropriate response out of the four provided to you. Question numbers 34 to 36 are short answer type questions carrying two marks each.
SECTION-A
1. What happens when hydrogen combines with oxygen in the presence of an electric current?
2. Why are endocrine glands called ductless glands?
3. The cost of production of electricity in a thermal power station located in Bihar / Jharkhand /
Orissa is lesser than in Gujarat / Maharashtra. Do you agree? Justify your answer.
4. A gas produced in the laboratory is highly soluble in water. Its colourless solution turns pink
when a few drops of phenolphthalein is added to it. What is the nature of this gas?
5. You are given several identical resistors each having resistance of 10 Ω and a maximum current
of 1 A is allowed to pass through each resistor. It is required to make a suitable combination of
these resistances of 5 Ω which can carry a curent of 4 A. Find the number of such resistances
which will be required.
6. Why is the inner wall of alimentary canal not digested although the digestive enzyme can digest
all the materials that make cells?
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7. The following diagram displays a chemical reaction. Observe carefully and answer the following
questions:
a. Identify the type of chemical reaction that will take place and define it. How will the colour
of the silver chloride change?
b. Write the chemical equation of the reaction that takes place.
c. Mention one commercial use of silver chloride.
8. A magnesium ribbon is burnt in oxygen to give a white compound X accompanied by emission
of light. If the burning ribbon is now placed in an atmosphere of nitrogen, it continues to burn
and forms a compound Y.
a. Write the chemical formula of X and Y.
b. Write a balanced chemical equation, when X is dissolved in water.
9. Think you are sitting in a chamber with your back to one wall. An electron beam, moving
horizontally from back wall towards the front wall, is deflected by a strong magnetic field to
your right side. What is the direction of magnetic field? Explain it diagrammatically.
10. Under what conditions permanent electromagnet is obtained if a current carrying solenoid is
used? Support your answer with the help of a labelled circuit diagram.
11. How are the wastes produced in nuclear power plants different from those produced in thermal
power plants? What happens to the waste of a nuclear power plant?
12. Mention why is it not possible to make use of solar cells to meet all our energy needs? State
three reasons to support your answer. Also mention three uses of solar cells.
13. Ramsingh is a villager who uses underground water for drinking. Fluoride ion, iron levels,
salinity and arsenic levels are high in ground water. Underground water also contains
microorganism which cause diseases like typhoid, cholera. His son Himanshu advised his father
to use boiled water and add one tablet of bleaching powder to one bucket of water.
a. What are harmful effects of F- in water?
b. What can we do for preservation of underground water?
c. What values are possessed by Himanshu?
14. Nervous and hormonal system together perform the function of control and coordination in
human beings. Justify the statement.
15. Find the equivalent resistance across the two ends A and B of this circuit.
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16. Several electric bulbs designed to be used on a 220 V electric supply line, are rated 10 W. How
many lamps can be connected in parallel with each other across the two wires of 220 V line if
the maximum allowed curent is 5 A?
17. A metal ‘X’ loses two electrons and a non-metal ‘Y’ gains one electron. Show the electron-dot
structure of compound formed between them. Is it ionic or covalent? Does it have high melting
point or low? Will it conduct electricity in solid state or in aqueous solution and why? Will it be
soluble in water?
18. An element A reacts with water to form a compound B which is used in white washing. The
compound B on heating forms an oxide C which on treatment with water gives back B. Identify
A, B and C and give the reactions involved.
19. Compare the functioning of alveoli in the lungs and nephrons in the kidneys with respect to their
structure and functioning.
20. What is endocrine system? What are its functions? Name the important endocrine glands present
in a human body. Draw a labelled diagram to show the positions of these endocrine glands in the
human body (male/female).
21. Two orse A and B were taken. On heating, ore A gives CO2 whereas, ore B gives SO2. What
steps will you take to convert them into metals?
22. A. Crystals of a substance changed their colour on heating in a closed test tube but regained it
after sometime when they were allowed to cool down. Name the substance and write its formula
and explain the phenomenon involved.
B. Name the compound whose one formula unit is associated with 10 water molecules. How is
it prepared? Give equations of related reactions. Give two uses of the compound.
23. Deduce the expression for the equivalent resistance of the parallel combination of three resistors
R1, R2 and R3. Consider the following electric circuit.
24. A student fixes a sheet of white paper on a drawing board. He places a bar magnet at the centre
of it. He spreinkles some iron filings uniformly around the bar magnet. Then he taps the board
gently and observes that the iron filings arrange themselves in a particular pattern.
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a. Why do the iron filings arrange in a pattern?
b. What is indicated by the crowding of iron filings at the end of the magnet?
c. What do the lines along which the iron filings align represent?
d. Draw a neat diagram to show the magnetic field lines around a bar magnet.
e. Write any two properties of magnetic field lines.
SECTION B
25. Aluminium sulphate and copper sulphate solutions were taken in two test tubes I and II
respectively. A few pieces of iron filings were then added to both the solutions. The four
students A, B, C and D recorded their observations in the form of a table as given below:
Student Al2(SO4)3 Solution (I) CuSO4 Solution (II)
A Colourless solution changes to light
green
Blue colour of the solution is retained
B Colour of the colourless solution
does not change.
Blue colour of the solution changes to
green
C Colourless solution changes to light
blue
Blue colour of the solution changes to
green
D Colour of the colourless solution
remains unchanged
Blue colour of the solution fades away
The correct set of observations has been recorded by student:
a. A b. B c. C d. D
26. During the experiment of heating of ferrous sulphate crystals, four students recorded their
observations as:
(i) green colour of crystals changes to brown black colour
(ii) brownish yellow gas is evolved
(iii) blue colour of crystals changes to green colour
(iv) smell of burning sulphur is felt
Which of the above observations are correct?
a. (i), (ii) b. (i), (iv) c. (ii), (iii) d. (iii), (iv)
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27. The figure below shows set ups for studying the reaction of zinc with sodium hydroxide.
The correct set up is:
a. I b. II c. III d. IV
28. To determine the equivalent resistance of a series combination of two resistors R1 and R2, a
student arranges the following set up:
Which of the following will be true for this circuit? It gives
a. incorrect reading for current I as well as potential difference V.
b. correct reading for current I but incorrect reading for potential difference V.
c. correct reading for potential difference V but incorrect reading for current I.
d. correct readings for both I and V.
29. A student has to connect 4 cells of 1.5 V each to form a battery of 6 V. The correct way of
connecting these cells is shown in figure:
a. A b. B c. C d. D
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30. In a voltmeter, there are 20 divisions between the 0 mark and 1 mark. The peast count of the
voltmeter is
a. 20 V b. 5.0 V c. 0.05 V d. 0.025 V
31. Four students focussed an epidermal peel of leaf under high power and made the following
sketches. Which one of the following is sketched correctly?
a. A b. B c. C d. D
32. Given below are randomly written steps for the experiments to show that light is necessary for
photosynthesis. Which one of the following is the correct sequence of steps for a successful run
of the experiment?
I. Pluck the experimental leaf.
II. Using strips of black paper, cover a portion of the leaf on both sides.
III. De-starch leaf of the potted plant.
IV. Test the experimental leaf for presence of starch.
V. Expose the plant to sunlight for four hours.
VI. Remove the black paper strips from the leaf.
a. I, III, II, IV, V, VI
b. II, I, V, VI, III, IV
c. III, II, V, I, VI, IV
d. V, I, II, III, IV, VI
33. Using the same number of given germinating gram seeds, two students A and B conduct the
experiment separately. Student A used a cotton plug to hold the bent tube in the mouth of the
flask. Student B used a rubber cork.
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After 4 hours, they noticed that
a. water level increased in the bent tube only of A.
b. water level increased in the bent tube only of B.
c. the cotton plug was wet.
d. The water in the beaker of tube turned milky.
34. A solution ‘X’ gives orange colour when a drop of universal indicator is added to it. On the other
hand, another solution ‘Y’ gives bluish-green colour when a drop of universal indicator is added
to it.
What are the types of solution ‘X’ and ‘Y’ and what type of pH would they have?
35. To determine the equivalent resistance of two resistors R1 and R2 when connected in parallel, a
student chooses the resistors to perform the experiment in such a way that R1 > R2. After taking
observations, he plots the V-I graph for the same. Draw the same V-I graph as he plotted by
taking ‘V’ on Y-axis and ‘I’ on X-axis for
(i) R1 and R2, and
(ii) R1 and R2, and their equivalent resistance on the same axis.
36. Why are germinating seeds taken in the experiment? What would happen if germinating seeds
are replaced by boiled seeds?
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