Question

D. Give two examples:-
1. Desirable changes
2. Slow changes
3. Fast changes
4. Irreversible physical changes
5. Reversible physical changes
6. Exothermic changes
7. Chemical changes
8. Endothermic changes​

Answer 1

Explanation:

2.slow changes : revolution and rotation

3.fast changes : tearing paper

4.melting of candle and decline in height

5.cutting of tree

6.rusting of iron

7.Boiling an egg. and Chemical battery usage.

8.melting ice, dry ice

1.Souring of milk. and Rusting of iron

Answer 2

Answer:

1) ripening of fruits , germination of seeds.

2) Rusting of iron, formation of day and night.

3) Burning of paper, Burning of a candle.

4) Breaking a glass, Chopping wood.

5) Melting of ice, boiling of water.

6) Rusting of iron, Setting of cement.

7) Rotting, burning.

8) Melting ice cubes, Evaporating liquid water.