(1) When a candle burns, both physical and chemical changes take place.
· Physical change is the melting of the wax.
· Chemical change is the burning of gas with the evolution of CO2.
(2) Digestion of food is another example where both physical and chemical changes occur simultaneously.
· Physical change is the breakdown of larger food molecules into simpler ones.
· The chemical change is the digestion of food by the action of HCl and enzymes.