2. Some of the differences between solids, liquids, and gases.

3. How to change solids to liquids and gases and vice versa.

4. The reason for the changes of size of a body on heating.

5. Why cooling a gas tends to change it to a liquid or a solid.

6. The actual size of molecules.

Which of the following changes are chemical and which physical?

Give reasons.

1. Melting of ice.

2. Burning of a candle.

3. Production of steam.