Changes Around Us Worksheet-1

Changes Around Us Worksheet-1

1. A change in which the original substance can be obtained back by reversing conditions is called

(a) Reversible change

(b) Physical change

(c) Irreversible change

(d) Both Reversible change & Physical change

2. When a little bit of curd is added to milk and it is left undisturbed for sometimes, the milk is changed into curd. It is an example of

(a) Fast chemical change

(b) Fast physical change

(c) Slow chemical change

(d) Slow physical change

3. In which of the following cases the heat energy is given out?

(i) When water boils

(ii) When ice melts

(iii) When water freezes to ice

(iv) When water vapor condenses to water

(a) In (i), (ii) & (iii)

(b) In (iii) only

(c) In (iv) only

(d) In both (iii) & (iv)

4. Growth of a tree is

(a) Physical change

(b) Reversible change

(c) Irreversible change

(d) Expansion process

5. Which is the non-periodic change amongst the following?

(a) Phases of moon

(b) Earthquake

(c) Change of seasons

(d) Beating of heart

6. Boiling, condensation, freezing, melting and evaporation are usually

(a) Physical changes

(b) Chemical changes

(c) Permanent changes

(d) Irreversible changes

7. Chemical change involves change in

(a) Color

(b) Temperature

(c) Energy

(d) All of these

8. Read the following statements and mark the correct option.

Statement – I : Some changes that result in the formation of new substances are called chemical changes.

Statement – 2 : Chemical changes are permanent changes.

(a) Both statements 1 and 2 are true and statement 2 is the correct explanation of statement 1.

(b) Both statements 1 and 2 are true but statement 2 is not the correct explanation of statement 1

(c) Statement 1 is true and statement 2 is false

(d) Statement 1 is false and statement 2 is true

9. Which of these is chemical change?

(a) Mixing paint colours

(b) Rubbing rust off a bridge

(c) Pressing fibers to make paper

(d) Baking a cake

10. Read the following phenomena carefully.

(i) Forest fire

(ii) Growth of plants

(iii) Low and high tides

(iv) Occurrence of a rainbow

(v) Earthquakes

(vi) Opening of a morning glory flower

Which of the above events can be referred to as periodic changes?

(a) (i), (ii) & (iii)

(b) (ii), (i), & (v)

(c) (iv), (v) & (vi)

(d) (iii) & (vi)

Answer Key:

(1)–(d), (2)–(c), (3)–(d), (4)–(c), (5)–(b), (6)–(a), (7)–(d), (8)–(b), (9)–(d), (10)–(d)