Question

What do you understand by the change of phase of a substance ?

Answer 1

There are four states of matter in the universe: plasma, gas, liquid and solid. But on earth there exists mostly three distinct phases or states: solid, liquid and gas.

A phase is the distinctive form of substance and matter can change among the phases. It may take extreme temperature, pressure or energy, but all matter can be changed.

There are six distinct change of phase which happens to different substances at different temperatures.

1) Freezing - Liquid to solid

2) Melting - Solid to Liquid

3) Condensation - Gas to Liquid

4) Vaporisation - Liquid to Gas

5) Sublimation - Solid to Gas (without going through liquid phase)

6) Deposition - Gas to Solid (without going into liquid phase)