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Physical changes

Those changes in which no new substances are formed, are called physical changes. The changes in state, size, shape and colour of a substance are physical changes. The properties such as state, size, shape and colour of a substance are called its physical properties. 

Those changes in which a substance undergoes a change in its physical properties are called physical changes.

The important characteristics of a physical change are as follows:

(1) No new substance is formed in a physical change.
(2) A physical change is a temporary change. A physical change can be easily reversed.
(3) Very little energy  is either absorbed or evolved in a physical change.
(4) A temporary change in colour may take place in a physical change.

Examples of physical changes :

Melting of ice (to form water)
Freezing of water (to form ice)
Boiling of water (to form steam
Condensation of steam (to form water
Evaporation of water to form water vapour
Condensation of water vapour (to form liquid water)