set – 1 - cbse online – cbse sample papers cbse exam pa:er 2017 ? science. ... practical skills....
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31/1 1 [P.T.O.
. . . . Roll No.
– II SUMMATIVE ASSESSMENT – II
SCIENCE
: 3 : 90
Time allowed : 3 hours Maximum Marks : 90
Series : HRK/C 31/1H$moS> Z§.H$moS> Z§.H$moS> Z§.H$moS> Z§. Code No.
- - Candidates must write the Code on
the title page of the answer-book.
SET – 1
• - 12
• - - -
• - 36
• , , , ,
• - 15 - 10.15 10.15 10.30 - -
• Please check that this question paper contains 12 printed pages.
• Code number given on the right hand side of the question paper should be written on the
title page of the answer-book by the candidate.
• Please check that this question paper contains 36 questions.
• Please write down the Serial Number of the question before attempting it.
• 15 minute time has been allotted to read this question paper. The question paper will be
distributed at 10.15 a.m. From 10.15 a.m. to 10.30 a.m., the students will read the
question paper only and will not write any answer on the answer-book during this period.
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31/1 2
::::
(i) , ,
(ii)
(iii)
(iv) -
(v) 1 3 ----
(vi) 4 6 ---- 30
(vii) 7 18 ---- 50
(viii) 19 24 ---- 70
(ix) 25 33
(x) 34 36 ----
General Instructions :
(i) The question paper comprises two Sections, A and B. You are to attempt both the
sections.
(ii) All questions are compulsory.
(iii) There is no choice in any of the questions.
(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 33 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.
(x) Question numbers 34 to 36 in Section B are two-marks questions based on
practical skills. These are to be answered in brief.
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31/1 3 [P.T.O.
–––– Section – A
1. 1
State Modern Periodic Law of classification of elements.
2.
? 1
Why should biodegradable and non-biodegradable wastes be discarded in two
different dustbins ?
3. 1
Define power of a lens.
4. ? 2
What is speciation ? State any two factors which could lead to speciation.
5. 2
List any four modes of asexual reproduction.
6. () ? 2
What are decomposers ? State the role of decomposers in the environment.
7. ? ? 3
What is scattering of light ? Why do the colour of clear sky appear blue ? Explain.
8.
+0.5 D , 3
Name the type of defect of vision a person is suffering from, if he uses convex lenses
in his spectacles for the correction of his vision. If the power of the lenses is +0.5 D,
find the focal length of the lenses.
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31/1 4
9. - (u), - (v) (f) u, v f 3
Draw a ray diagram to show the formation of real image of an object when refraction
of light takes place through a convex lens. Mark as per the new Cartesian sign
convention the object-distance (u), image distance (v) and the focal length (f) and
also write the relation between u, v and f.
10. 3
State Snell’s law of refraction of light. Express it mathematically. Write the
relationship between absolute refractive index of a medium and speed of light in
vacuum.
11. ? ? 3
What are covalent compounds ? How are they different from ionic compounds ? List
any two properties of covalent compounds.
12. H2SO4
(i)
(ii) H2SO4
(iii) 3
Ethanoic acid reacts with absolute ethanol in the presence of Conc. H2SO4 to form a
compound
(i) Write the smell and class of compounds to which this compound belong.
(ii) Write the chemical equation for the reaction and state the role of Conc. H2SO4
in the reaction.
(iii) Write one use of the product of this reaction.
13. , P ( 17) Q ( 19), 3
Write the electronic configurations of two elements P (atomic number 17) and
Q (atomic number 19) and determine their group numbers and period numbers in the
Modern Periodic Table.
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31/1 5 [P.T.O.
14. ‘X’ (2, 8, 2) , (NO3)– (SO4)2– -
(i) ‘X’ ? (ii) ‘X’
? 3
An element ‘X’ with electronic configuration (2, 8, 2) combines separately with two
radicals, (NO3)– and (SO4)2–.
(i) Is ‘X’ a metal or a non-metal ? Write the nature of its oxide.
(ii) Write the formula of the compounds of ‘X’ formed by the combination of these
radicals. Are these compounds covalent or electrovalent ?
15. A, B C - 3
Name the three parts A, B and C of the flower shown in the figure and state one
function of each.
16. 3
(i) ?
(ii) (iii) - The teacher explained in the class that reproduction is the process by which
organisms increase their population. Manoj wanted to know more about the
reproductive-health. Therefore, the teacher also explained in the class about the
diseases that can be transmitted, if proper care is not taken.
(i) Why is the increasing human population a cause of concern for all of us ?
(ii) Name two diseases that can be sexually transmitted.
(iii) State one value each displayed by Manoj and his teacher.
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31/1 6
17. ? ? 3
What are homologous organs ? Give one example. Can the wings of a butterfly and the
wings of a bat be regarded as homologous ? Give reason in support of your answer.
18. () () , F1 F1
, F2
(i) F1 ?
(ii) F2
(iii) F1 , F2
3
If we cross-bred tall (dominant) pea plant with pure-bred dwarf (recessive) pea plant,
we will get plants of F1 generation. If we now self-cross the pea plant of F1
generation, we obtain pea plants of F2 generation.
(i) What do the plants of F1 generation look like ?
(ii) State the ratio of tall plants to dwarf plants in F2 generation.
(iii) State the type of plants not found in F1 generation but appeared in F2
generation. Write the reason for the same.
19. 5
State the laws that are followed when light is reflected by spherical mirrors. Draw a
ray diagram to show the formation of image of an object placed infront of a convex
mirror. List two characteristics of the image formed. Briefly explain one use of
convex mirrors.
20. ? ? 5
What is spectrum of white light ? Why do different coloured rays deviate at different
angles on passing through a glass prism ? Explain the method of recombining the
different components of white light.
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31/1 7 [P.T.O.
21. (a)
(b)
(c) ? 5
(a) Write a chemical test to distinguish between saturated and unsaturated
hydrocarbons.
(b) Name the products formed when ethane burns in air. Write chemical equation
for the reaction showing various types of energies liberated.
(c) Write the reaction between methane and chlorine in the presence of sunlight.
Why is this reaction considered a substitution reaction ?
22. (a) :
(i)
(ii)
(iii)
(b) 5
(a) Write the functions of the following parts in human female reproductive system :
(i) Ovary
(ii) Fallopian tube
(iii) Uterus
(b) Describe the structure and functions of placenta.
23. ? ? 5
Define evolution. How does it occur ? Explain how fossils provide evidences in
support of evolution.
24. (a) ,
(b) ? 5
(a) In the context of conservation of natural resources, explain the terms reduce,
recycle and reuse.
(b) Why is conservation of water necessary ? State any four reasons.
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31/1 8
–––– Section – B
25. ? 1
(a) (A) (b) (B)
(c) (C) (d) (D)
A student is performing the experiment of determining the focal length of a given
concave mirror by focussing a distant tree on a screen. Which one of the following
kinds of images he is likely to obtain on the screen ?
(a) (A) (b) (B)
(c) (C) (d) (D)
26. , :
(a) , ,
(b) , ,
(c) , ,
(d) , , 1
A student has focussed on the screen a distant building using a convex lens. If he has
selected a blue coloured building as object, select from the following options the one
which gives the correct characteristics of the image formed on the screen.
(a) Virtual, erect, diminished and green shade
(b) Real, inverted, diminished and in violet shade
(c) Real, inverted, diminished and in blue shade
(d) Virtual, inverted, diminished and in blue shade
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31/1 9 [P.T.O.
27. A, B, C D ?
(a) (A) (b) (B)
(c) (C) (d) (D) 1
Study the following four experimental setups by four students A, B, C and D showing
the incident ray to trace the path of a ray of light through a glass slab. Which of these
will get the best result ?
(a) (A) (b) (B)
(c) (C) (d) (D)
28. :
(a) ∠i, ∠A, ∠D (b) ∠i, ∠r, ∠D
(c) ∠i, ∠e, ∠A (d) ∠r, ∠e, ∠D 1
Study the following diagram and select the option having correctly marked angles
s
(a) ∠i, ∠A, ∠D (b) ∠i, ∠r, ∠D
(c) ∠i, ∠e, ∠A (d) ∠r, ∠e, ∠D
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31/1 10
29. ?
(a) 20% Ca(OH)2 (b) 20% NaOH
(c) 30% Mg(OH)2 (d) 10% Ca(OH)2 1
You have neem oil in a beaker. In order to study saponification reaction, which of the
following chemical substances would you add to this oil ?
(a) 20% Ca(OH)2 (b) 20% NaOH
(c) 30% Mg(OH)2 (d) 10% Ca(OH)2
30.
(a)
(b)
(c)
(d) 1
Select the correct statement about the properties of acetic acid.
(a) It smells like vinegar and turns red litmus to blue.
(b) It is insoluble in water and turns blue litmus to red.
(c) It is soluble in water and turns red litmus to blue.
(d) It smells like vinegar and turns blue litmus to red.
31. A, B, C D
A NaCl, B CaCl2, C MgCl2 D KCl
, ( ) ?
(a) A B (b) B C
(c) C D (d) A D 1
You have four test tubes A, B, C and D filled with aqueous solution of same
concentration but of different salts. In A solution of NaCl, B solution of CaCl2,
C solution of MgCl2 and D solution of KCl is filled. If you add equal amounts of a
soap solution to each test tube and shake the contents well, in which of the test tubes
will scum (insoluble substance) be obtained ?
(a) A and B (b) B and C
(c) C and D (d) A and D
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31/1 11 [P.T.O.
32.
, , , , ,
–
(a) , ,
(b) , ,
(c) , ,
(d) , , 1
On observing an embryo of a pea seed, a student listed its various parts as given
below :
Micropyle, Cotyledon, Plumule, Testa, Radicle, Tegmen
On examining the list the teacher remarked that out of these only three parts belong to
embryo. Select these three parts :
(a) Testa, Radicle, Cotyledon
(b) Tegmen, Radicle, Micropyle
(c) Cotyledon, Plumule, Radicle
(d) Cotyledon, Plumule, Testa
33. A, B, C D
?
A.
B.
C.
D. ,
(a) A (b) B (c) C (d) D 1 Four students A, B, C and D listed the following sets of organs of different organisms
as homologous organs. Who was correct ?
A. wings of a bat and wings of a butterfly
B. wings of a pigeon and wings of a bat
C. wings of a pigeon and wings of a butterfly
D. forelimbs of a cow, a duck and a lizard
(a) A (b) B (c) C (d) D
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31/1 12
34. (i) (ii)
, ?
, 2
If you add a few drops of acetic acid to a test tube containing (i) distillated water and
(ii) aqueous solution of sodium hydrogen carbonate, what would you observe ? If a
reaction takes place in any one of the above two cases, list its two observations.
35.
2
Draw a labelled diagram to show that particular stage of binary fission in Amoeba in
which its nucleus elongates and a constriction appears in its cell membrane.
36. 2.0 cm 10 cm
(O) 20 cm
,
2
An object of height 2.0 cm is placed on the principal axis of a convex lens of focal
length 10 cm. The distance of the object from the optical centre (O) of the lens is
20 cm. Choose a proper scale and draw a ray diagram to find the position, nature and
size of the image. Also measure and write the size of the image and its distance from
the optical centre of the lens.
____________
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Outside Delhi – 31/1 Page 1
Strictly Confidential- (For Internal and Restricted Use Only) Secondary School Examination SUMMATIVE ASSESSMENT - II
July 2017
Marking Scheme – Science (Outside Delhi) 31/1 1. The Marking Scheme provides general guidelines to reduce subjectivity in the marking. It carries
only suggested value points for the answer. These are only guidelines and do not constitute the complete answer. Any other individual response with suitable justification should also be accepted even if there is no reference to the text.
2. Evaluation is to be done as per instructions provided in the Marking Scheme. It should not be done according to one's own interpretation or any other consideration. Marking Scheme should be strictly adhered to and religiously followed.
3. If a question has parts, please award marks in the right hand side for each part. Marks awarded for different parts of the question should then be totalled up and written in the left hand margin.
4. If a question does not have any parts, marks be awarded in the left hand side margin.
5. If a candidate has attempted an extra question, marks obtained in the question attempted first should be retained and the other answer should be scored out.
6. Wherever only two/three of a 'given' number of examples/factors/points are expected only the first two/three or expected number should be read. The rest are irrelevant and should not be examined.
7. There should be no effort at 'moderation' of the marks by the evaluating teachers. The actual total marks obtained by the candidate may be of no concern of the evaluators.
8. All the Head Examiners / Examiners are instructed that while evaluating the answer scripts, if the answer is found to be totally incorrect, the (X) should be marked on the incorrect answer and awarded ‘0’ marks.
9. ½ mark may be deducted if a candidate either does not write units or writes wrong units in the
final answer of a numerical problem.
10. A full scale of mark 0 to 100 has to be used. Please do not hesitate to award full marks if the answer deserves it.
11. As per orders of the Hon’ble Supreme Court the candidates would now be permitted to obtain photocopy of the Answer Book on request on payment of the prescribed fee. All Examiners/Head Examiners are once again reminded that they must ensure that evaluation is carried out strictly as per value points given in the marking scheme.
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Outside Delhi – 31/1 Page 2
MARKING SCHEME CLASS X – OUTSIDE DELHI
Code No. 31/1
Expected Answer/ Value point Marks Total
SECTION – A
Q1. Properties of elements are a periodic function of their atomic number. 1 1 Q2. i) Saves time/ energy in segregation
ii) Biodegradable items can be directly sent for composting iii) Non–biodegradable items can be sent for appropriate reuse/ recycle ½ x 2 1
(any two) Q3. Ability of a lens to converge or diverge light rays./ It is reciprocal of focal
length in meters./ It is the degree of convergence or divergence of light rays
1
1
Q4. Speciation – Origin of a new species from pre-existing one. 1 Factors – Mutation, Genetic drift, Geographical isolation,
Reproductive isolation. ( any two) ½ x 2 2
Q5. Fission, Fragmentation, Regeneration, Budding, Vegetative Propagation,
Spore formation. ( any four) ½ x 4 2 Q6. Organisms that breakdown complex organic matter/ the dead remains
and waste products of organisms. 1 Role: Help in recycling of nutrients in nature.
Replenishment of soil nutrients ( any one ) 1 2 Q7. The phenomenon in which a part of the light incident on a particle is
redirected in different directions. 1 When sunlight passes through the atmosphere, its fine particles scatter
the blue colour more strongly than red. The scattered blue light enters our eyes. Hence the sky appears blue. 2 3
Q8. Hypermetropia/ Longsightedness 1
1001
Pf 100
5.01f = 200 cm
1
2 Q9.
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Outside Delhi – 31/1 Page 3
Note: Give full credit if candidate draws ray diagram. for any other position of the object Diagram with direction of rays
Marking ‘u’, ‘v’ and ‘f’ in the diagram
v
1
u
1 =
f
1
1 ½ x 3
½
3
Q10. The ratio of sine of angle of incidence to the sin of angle of refraction is a
constant, for the light of a given colour and for the given pair of media. 1
r
i
sinsin
= constant 1
m
mv
cn
mediumtheinlightofSpeedair/vacuuminlightofSpeed
1
3
Q11. The compounds that are formed due to sharing of electrons between
two atoms/ compounds having covalent bonds. 1 Ionic compounds are formed due to transfer of electrons from one
atom to another / compounds having ionic bonds/ compounds having attraction between oppositely charged ions 1
i) They are poor conductors of electricity ii) They have low melting and boiling point. ( or any other) ½ , ½ 3
Q12. i) Pleasant/ fruity smell; Esters
ii) CH3COOH + C2H5OHOHSOHconc.
2
42
CH3COOC2H5
CONC. H2SO4 acts as a catalyst/ dehydrating agent
iii) Used in perfume industry / as flavouring agent
½ , ½ 1 ½ ½ 3
Q13. Electronic configuration of ‘P’ : 2,8,7
Group number: 17 Period number: 3 Electronic configuration of Q: 2,8,8,1 Group number : 1 Period number: 4 ½ x 6 3
Q14. i) Metal, Basic
ii) X(NO3)2, XSO4 These compounds are ionic/ electrovalent
½ , ½ ½ , ½
1 3 Q15. A Anther: Produces pollen/ male gamete
B Style: Carries the pollen to the ovary C Ovary: Produces ovules/ female gamete
½ x 6
3
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Outside Delhi – 31/1 Page 4
Q16. i) Because natural resources are limited, and it would be difficult to sustain a large population on limited resources
ii) HIV-AIDS, Syphilis, Gonorrhoea, Warts ( any two) iii) Manoj- Inquisitive, understands the need for healthy living (any
one) Teacher – concerned, dutiful ( any one)
1
½ , ½
½ ½ 3
Q17. Homologous Organs - Organs with similar basic structure/ origin but
modified to perform different functions. Example: forelimbs of various vertebrates ( or any
other) Wings of a butterfly and the wings of a bat cannot be regarded as
homologous organs Reason: Though they perform the similar function, they have
different origin/ basic structure
1
½ ½ 1 3
Q18. i) Tall
ii) 3:1 iii) Dwarf
Reason: Being a recessive trait, dwarfness can only be expressed in the absence of dominant trait/ in its pure form.
1 ½ ½ 1
3
Q19. (i) The incident ray, the normal to the mirror at the point of incidence and the
reflected ray, all lie in the same plane, and (ii) The angle of incidence is equal to the angle of reflection
½, ½
2
Virtual, erect, diminished ( Any two) 1 Rear view mirror as it gives wider field view/ Used in shops to avoid theft.
( Any one) 1 5 Q20. The band of the coloured components of white light.
Refractive index/ speed of light is different for different colours. By placing a second identical prism in an inverted position with
respect to first prism (Proper explanation is to be given)./diagram with labelling
1 1 3
5 Q21. a) Bromine water gets decolourised by unsaturated hydrocarbons but 1 5
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Outside Delhi – 31/1 Page 5
remains unaffected (reddish brown) by saturated hydrocarbons. (or any other test)
b) Carbon dioxide/ CO2 and Water/ H2O 2C2H6 + 7O2 4CO2 + 6H2O + Heat + Light
c) CH4 + Cl2 sunlight CH3Cl + HCl Because hydrogen atom is replaced by chlorine atom.
1 1 1 1
Q22. a) i) Ovary: Produces female gamete / ovum
Produces oestrogen/ female sex hormones ii) Fallopian tube: Carries ovum from ovary to the uterus
Site of fertilization iii) Uterus: Site for implantation and nourishment of the future embryo.
½ , ½
½ , ½ 1
b) Structure of placenta: Disc like structure embedded in the uterine wall. It has villi on the embryo’s side and blood species on the mother’s side which surround the villi Function of placenta: Transports oxygen and nutrition from the mother’s blood to the embryo. Removes the excretory substances from embryo into the mother’s blood
½ , ½
½ , ½ 5 Q23. Evolution: Gradual accumulation of variations and its selection by
nature leading to formation of new species. Variations may arise in a population due to mutations or sexual
reproduction. Sub-populations are formed due to genetic drift and geographical isolation. When natural selection acts on them, most suitable variation survives leading to evolution of a new species.
Fossils provide missing link between the species /who has evolved from whom. They provide information about prehistoric organisms.
1 2
1, 1
5
Q24. a) i) Reduce: Less use of natural resources/ avoid wastage of food, water,
electricity etc. ii) Recycle: Collection of materials like plastic, glass, metals, paper etc. and recycle these materials to make required items instead of synthesizing fresh ones. This would save natural resources iii) Reuse: Still better than recycling as no energy is required here and the already used things /items are used again and again.
1 1 1
b) i) Essential for living organisms ii) It has limited availability iii) Conservation of water allows its equitable distribution. iv) Essential for sustainable development (any other relevant point) ½ x 4 5
SECTION – B 25) B 26) C 27) D 28) A 29) B 30) D 31) B 32) C 33) D
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Q34. No reaction with distilled water. Chemical reaction occurs with solution of NaHCO3 Two Observations:
i) Evolution of a colourless, odourless gas. ii) The gas is evolved with brisk effervescence
½ ½
½ ½ 2
Q35.
Diagram Labelling
½ ½ x 3 2
Q36.
Diagram
Correct labeling 1
½, ½ 2
20 cm
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