Changes Around Us Book Back Answers & Guides

Unit 3 > Science > Class 6 > Samacheer Kalvi - English Medium

    Choose the correct answer

  • 1. When ice melts to form water, change occurs in its

    a. position

    b. colour

    c. state

    d. composition

    Correct answer:

    c. state

    View explanation


  • 2. Drying of wet clothes in air is an example of

    a. Chemical change

    b. Undesirable change

    c. irreversible change

    d. physical change

    Correct answer:

    d. physical change

    View explanation


  • 3. Formation of curd from milk is

    a. a reversible change

    b. a fast change

    c. an irreversible change

    d. an undesirable change

    Correct answer:

    c. an irreversible change

    View explanation


  • 4. Out of the following an example of a desirable change is

    a. rusting

    b. change of seasons

    c. earthquake

    d. flooding

    Correct answer:

    b. change of seasons

    View explanation


  • 5. Air pollution leading to Acid rain is a

    a. reversible change

    b. fast change

    c. natural change

    d. human made change

    Correct answer:

    d. human made change

    View explanation


  • Fill in the blanks

  • 1. Magnet attracts iron needle. This is_______change. (a reversible / an irreversible)

    Correct answer:

    a reversible

    View explanation


  • 2. Boiling of egg results in___________ change. (a reversible / an irreversible)

    Correct answer:

    an irreversible

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  • 3. Changes that are harmful to us are__________ . (desirable / undesirable)

    Correct answer:

    undesirable

    View explanation


  • 4. Plants convert Carbon-di-oxide and water into starch. This is an example of__________change. (natural / human made)

    Correct answer:

    natural

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  • 5. Bursting of fire crackers is a --------------- change whereas germination of seeds is a__________change. (slow / fast)

    Correct answer:

    fast,slow

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  • True or false

  • 1. Growing of teeth in an infant is slow change.

    Correct answer:

    True

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  • 2. Burning of match stick is a reversible change.

    Correct answer:

    False

    Correct Statement: The match stick undergoes a chemical change. It is an irreversible change

    View explanation


  • 3. Change of New moon to Full moon is human made.

    Correct answer:

    False

    Correct Statement: Change of New moon to Full moon is a natural change

    View explanation


  • 4. Digestion of food is a physical change.

    Correct answer:

    False

    Correct Statement: The digested food undergoes chemical change

    View explanation


  • 5. In a solution of salt in water, water is the solute

    Correct answer:

    False

    Correct Statement: In a solution of salt in water, water is a solvent

    View explanation


  • Analogy

  • 1. Curdling of milk : irreversible change :: Formation of clouds : ________change

    Correct answer:

    reversible

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  • 2. Photosynthesis : __________ change :: burning of coal : Human made change

    Correct answer:

    natural

    View explanation


  • 3. Dissolving of glucose : reversible change :: Digestion of food:___________ change

    Correct answer:

    irreversible

    View explanation


  • 4. Cooking of food : desirable change :: decaying of food : _________change

    Correct answer:

    undesirable

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  • 5. Burning of matchstick :_______ change: Rotation of the Earth : Slow change

    Correct answer:

    fast

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  • Circle the odd one out. Give reason for your choice

  • 1. Growth of a child, Blinking of eye, Rusting, Germination of a seed

    Correct answer:

    Rusting (Rusting is undesirable change. Others three are desirable changes.)

    View explanation


  • 2. Glowing of a bulb, lighting of a Candle, breaking of a coffee mug, curdling of milk

    Correct answer:

    Breaking of a coffee mug (Breaking of a coffee mug is undesirable change. Others three are desirable changes.)

    View explanation


  • 3. Rotting of an egg, condensation of water vapour, trimming of hair, Ripening of fruit

    Correct answer:

    Rotting of an egg (Rotting of an egg is undesirable change. Others three are desirable changes.)

    View explanation


  • 4. Inflating a balloon, popping a balloon, fading of wall paint, burning of kerosene

    Correct answer:

    Inflating a balloon (Inflating a balloon is a reversible change. Others three are irreversible changes)

    View explanation