Changes Around us - Questions

Q25. Write reversible or irreversible for each of the following change:

S.No.

Change

Type of Change

1

Cutting of a piece of wood

 

2

Melting of ice cube

 

3

Dissolving salt in water

 

4

Cooking of Dal

 

5

Ripening of fruit

 

6

Souring of milk

 

7

Boiling of water

 

8

Stretching of rubber band

 

9

Making of chapatti

 

10

Grain to its flour

 

11

Boiling of egg

 

12

Dry to wet cloth

 

13

Rice to rice flour

 

14

Cold water to hot water

 

15

Batter to idli

 

16

Woollen yarn to knitted sweater

 

17

Straight string to a coiled string

 

18

Bud to flower

 

19

Milk to paneer

 

20

Cow dung to biogas

 

21

Ice cream to molten ice cream

 

 

 

Q26. Classify the change as slow or fast change.

S.No.

Change

Type of Change

1

Spinning of top

 

2

Change of day and night

 

3

Formation of curd from milk

 

4

Burning of paper

 

5

Change in weather

 

6

Melting of ghee on heating

 

 

Q27. What is evaporation? What kind of change it is? Give a reason in support of your answer.

 

Q28. How curd is formed? Is it a reversible change?

 

Q29. Iron blade of tools has a ring in which the wooden handle is fixed. Why the ring is made slightly smaller in size than wooden handle?

 

Q30. Why a thick layer of Plaster of Paris is applied over the bandage to keep the fractured bone immobilized?

 

Q31. Differentiate between toy aeroplane made by folding paper and toy aeroplane cutout. 

 

Q32. Differentiate between making chocolates of different shapes and baking cakes of different shapes.

 

Last modified: Saturday, 20 October 2018, 10:21 PM