Classify the following as a physical or a chemical change :
(a) Drying of wet clothes
(b) Manufacture of salt from seawater.
(c) Butter getting rancid
(d) Boiling of water
(e) Burning of paper
(f) Melting of wax
(g) Burning of coal
Some changes are given below.
(a) Freezing of water
(b) Melting of ice
(c) Boiling of water
Are these considered as physical changes? If yes, give the reason.