Question

Give one example for each statement (1)Change which occurs on heating but can be reversed (2)Change which occurs on heating but cannot be reversed

Answer 1

1) burning of candle

2) Cooking of food

Answer 2

1) When you heat ice, it turns to water. It can be reversed when you freeze water, it will turn back to ice. Thus, it is reversible change.

2) When you burn paper, it turns to ash. It can't be reversed, thus, it is irreversible change.