CBSE Sample Paper for Class X Science

                                            Time: 3hrs

                                            MM: 90

General instructions:

  1.     The question paper comprises of two sections, A & B. you are to attempted both the sections.
  2. All the questions are compulsory.
  3. There is no overall choice. However, internal choice has been provided in all the five questions of five marks category. Only one option in each question is to be attempted.
  4. All the questions of sections A and all sections of section B are to be attempted separately.
  5. Question numbers 1 to 3 in section A are 1 mark questions. These are to be answered in one word or one sentence.
  6. Question number 4 to 7 are 2 mark questions, to be answered in about 30 words.
  7. Question numbers 8 to 19 are 3 mark questions, to be answered in about 50 words.
  8. Question numbers 20 to 24 are 5 mark questions, to be answered in about 70 words.
  9. Question numbers 25 to 42 is section B are multiple choice question on practical skills. Each question is 1 mark question. You are to choose one most appropriate response of the options provided to you.

Section – A

  1. List the three phenomenon of light responsible for formation of rainbow in the sky.
  2. Why is DNA copying an essential part of the process of reproduction?
  3. List any two common methods by which solid wastes of urban areas are disposed off.
  4. Why do we see stars twinkling whereas planets do not twinkle?
    1. i)     What is meant by power of accommodation of eyes?

          ii)     How does the focal length of the eye lens change when we shift looking from a distant object to a nearby object?

      1. i)     Why are coal and petroleum called as fossil fuel?

            ii)    Name the two elements which are present both in CNG and petroleum?

      2. i)     What is the position of hydrogen in the modern periodic table?
    2. Where are isotopes of the same element having different atomic masses placed in the periodic table?
      1. Pure breed pea plants A are crossed with pure breed pea plant B. it is found that the plants who look

    like A do not appear in F1 generation but B re-emerge in F2 generation. Which of the plants A and

    B (i) tall (ii) dwarf ? Give reason for your answer.

  1. A student sitting in the last row of the classroom is not able to read clearly the writing on the

    blackboard :

  1.     Name the type of defect vision he is suffering from
  2. How can this defect be corrected?
  3. a)     Name the compound CH3COOH and identify its functional group.
  1. Give a chemical test to identify this compound.
    1.     Name the gas evolved when this compound acts on solid carbonate. How would you identify this gas.
    2. a)     Explain the terms (i) implantation (ii) placenta

          b)     What is the average duration of human pregnancy?

          c)     What happen when the egg is not fertilized?

    12.     a)     A spherical mirror A forms an erect image of an object, a spherical mirror B forms erect as well as inverted image of an object. Name the types of the spherical mirror A and B.

        b)     What is the relation between the focal length and radius of curvature of a spherical mirror? If the radius of a curvature of a spherical mirror is 25cm, what is focal length?

13.     An organic compound A is an essential constituent of wine and beer. Oxidation of A yield an organic acid B which is present in vinegar. Name the compounds A and B and write their structural formula. What happens when A and B react in the presence of an acid Catalyst? Write the chemical equation for the reaction.

  1. Which of the following are homologous and which are the analogous? Give reasons

    (i)     Trunk of the elephant and hand of a chimpanzee

    (ii)     Wing of a bird and wing of a bat.

    (iii) Scales of fishes and shell of mollusks

  2. Lit is desired to obtain an erect image of an object, using an concave mirror of focal length 20cm.

    (i)     What should be the range of the distance of object from the mirror?

    (ii)     Will the image be bigger or smaller than the object?

    (iii) Draw a ray diagram to show the image formation in this case.

    16.     a) Why does carbon form largest number of compounds?

    (b) Why are some of these called saturated and other unsaturated compounds?

    (c) Which of these is more reactive?

    17.    Write three advantages of constructing dams across the rivers?

    18.     (a) State two effects produced by scattering of light by the atmosphere?

    (b) Why are danger signal lights red in colour?

    (c) What would the sky look like if the earth had no atmosphere?

    19.     The electronic configuration of these elements X, Y and Z are given below?                         X         2

    Y             2,6

    Z         2,8,2

    1.     Which element belongs to second period ?
    2. Which element belongs to second group?

      iii) Which element belongs to 18th group?

    20.     (a) What are the main reasons why human beings are over-exploiting the forests?

    (b) What are the effects of damages?

    (c) Names the different measures taken up for the conservation of forests?

    21.     a)     Why do we classify elements ?

    b) What were the two criteria used by Mendeleev in creating his periodic table?

    c) In Mendeleev’s periodic table, why was there no mention of noble gasses like helium, neon and argon?

    d) Why did Mendeleev leave some gaps in his periodic table?

    e) Would you place the two isotopes of chlorine, CI-35 in different slot because of their different atomic masses or in the same slot because their chemical properties are the same ? Justify your answer.

    22.     Names the type of mirror(s) that should be used to obtain:

    (a) A magnified and virtual image            (b) A diminished and virtual image of an object.

    (c) Draw labeled ray diagrams to show the formation of the required image in each of the above two cases .Which of these mirrors could also form a magnified and real image of the object? State the position of object for which this could happen.

    23     a) Define homologous series of organic compounds. Mention any two characteristics of homologous series.

        b)     Name the compound formed on heating ethanol at 443k with excess of conc.H2S04.

        c)     Describe a chemical test to distinguish between ethanol and ethanoic acid.

    24.     (a)     Give an example of bisexual flower. What is its female reproductive part known as?

        (b) Draw a diagram of its longitudinal section showing the process of germination of pollen on stigma and label the following on it.

        (c) Pollination may occur without fertilization but fertilization will not take place without pollination. Give reason.


    25.     “An iron nail was suspended in copper sulphate solution and kept for a while”. The solution

        a)     remained blue and a coating was formed on the nail

        b) turned green and a coating was formed on the nail

        c) remained blue and ho coating was formed on the nail

        d) turned green and no coating was formed on the nail

    26.     A student put a big iron nail each in 4 test-tube containing solutions of zinc sulphate, aluminum sulphate, copper sulphate, and iron sulphate. A reddish brown coating was observed only on the surface of iron nail which was put in the solution

    a) Zinc sulphate b) iron sulphate        c) Copper sulphate    d) aluminum sulphate

    27.     Four test tubes were taken and marked as A, B, C & D respectively. 2mLod solution of Al2(S04)3 in water was filled in each of the test tubes. Clean piece of metal zinc was placed in A, clean iron nail in B, clean copper wire in C & a clean aluminium wire in D. It was observed that no change occurred in any of the test tubes. The correct inference drawn is:

    (a) Zinc is more reactive than Aluminium

    (b) Zinc is more reactive than Copper

    (c) Copper is more reactive than Aluminium

    (d) Zinc, Iron & copper is more reactive than Aluminium

    28.     Which of the following reagents gives brisk effervescence with EthanoicAcid?

    (a) Calcium Hydroxide                (b) Sodium Chloride

    (c) Sodium Bicarbonate                (d) Ammonium Chloride

    29.     A student soaked 5g of raisins in beaker A containing 25ml of ice chilled water and another 5g of raisins in beaker B containing 25ml of tap water at room temperature. After one hour, the student observed that

    (a) water absorbed by raisins in beaker A was more than that absorbed by raisins in beakerB

    (b) water absorbed by raisins in beaker B was more than that absorbed by raisins in beakerA

    (c) the amount of water absorbed by the raisins of both beakers A and B was equal.

    (d) No water was absorbed by raisins in either of the beakers A and B

    30.     When a stopper of a bottle containing a colourless liquid was removed, the bottle gave out a smell like that of vinegar. The liquid in the bottle could be

    a) Hydrochloric acid solution            b) sodium hydroxide.solution

    c) Acetic acid                     d) saturated sodium bicarbonate

    31.     In amoeba, asexual reproduction by multiple fission

    a) never take place                b) sometimes takes place

    c) take place when amoeba wishes

    d) take place during unfavorable environment conditions

    32.     For determining the percentage of water absorbed by raisins in a given time, apart from water, raisins and a watch, we shall also require ,

    (a)     a beaker, a graduated cylinder, a thermometer ,a filter paper.

    (b) a watch glass, a graduated cylinder, a thermometer, a weighing balance.

    (c) a beaker, a thermometer, a filter paper, a weighing balance.

    (d) a graduated cylinder, a thermometer, a weighing balance.

    33.     The inner surface of a stainless steel spoon behaves as__________.

    (a) concave mirror.                (b) convex mirror.

    (c) plane mirror                    (d) neither concave nor convex

    34.     A student obtains a blurred image of an object on a screen by using a concave mirror. In order to obtain a sharp image on the screen, he will have to shift the mirror

    (a) towards the screen

    (b) away from screen

    (c) either towards or away from screen, depending upon the position of the object

    (d) to a position very far away from the screen

    35.     In an experiment to determine the focal length of a convex lens, a student obtained a sharp inverted image of a distant tree on the screen behind the lens. She then removed the screen and looked through the lens in the direction of the object. She will see

    (a) an inverted image of the tree at the focus of the lens

    (b) no image as the screen has been removed

    (c) a blurred image on the wall of the lab

    (d) an erect image of the tree on the lens

    36.     A student is to find the focal length of a (i) concave mirror, (ii) convex lens by using a distant object. We will observe that the screen is on the same side as the object

    (a) in both cases                    (b) in neither of the two cases

    (c) in case (i) but not in case(ii)            (d) in case (ii) but not in case (i)

    37.     A student suggested the following Guidelines to his friend for doing the experiment on dressing the path of a ray of a light, passing through a rectangular slab, for three different angles of incidence:

    A) Draw outline of the glass slab at three positions on the drawing sheet.

    B) Draw normal on the top side of these outlines near their left end

    C) Draw the incident rays on the three outlines in direction, making angles of 30o, 45c 60o with the normal drawn

    D) Fix two pins vertically on each of these incident rays at two points nearly 1 cm apart.

    E) Look for the images of the feet of these pins while fixing two pins, from other side, to get the refracted ray

    When he showed these guidelines to his teacher, the teacher told him that two of them need to be corrected and modified. These two Guidelines are

    (a) B & C            (b) C & D        (c) D&E        (d) B&D

    38.     If you find the focal length of a concave and convex mirror respectively which appears to be the same say 20 cm. If you face the mirror to distant object, then the size of the image will be

    (a) same in both the mirrors.            (b) smaller in concave mirror

    (c) bigger in convex mirror            (d) bigger in concave mirror

    39.     Which one of the following is depicted in the sketch of a slide shown below?

    (a) Binary fission in yeast            (b) Budding in yeast

    (c) Binary fission in amoeba            (d) Budding in amoeba

    40.     Which one out of the following diagrams correctly depicts an amoeba undergoing binary fission?

    (a) I          (b) II          (c) III (d) IV

    41.     Acetic acid is:

    (a) Colourless, pungent smelling liquid        (b) Colourless, sweet smelling liquid

    (c) Green coloured liquid having pungent smell     (d) none of the above

    42.     If the object is at 2F of a convex lens, and then the image is at:

    (a) 2F             (b) F            (c) infinity      (d) Between F and 2F


Physics X | Light – Reflection and Refraction | REFLECTION OF LIGHT


A highly polished surface, such as a mirror, reflects most of the light falling on it. You are already familiar with the laws of reflection of light.

Let us recall these laws –

(i) The angle of incidence is equal to the angle of reflection, and

(ii) The incident ray, the normal to the mirror at the point of incidence and the reflected ray, all lie in the same plane.

These laws of reflection are applicable to all types of reflecting surfaces including spherical surfaces. You are familiar with the formation of image by a plane mirror. What are the properties of the image? Image formed by a plane mirror is always virtual and erect. The size of the image is equal to that of the object. The image formed is as far behind the mirror as the object is in front of it. Further, the image is laterally inverted.

How would the images be when the reflecting surfaces are curved? Let us explore.

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