Q.5 When a candle burns, both physical and chemical changes take place. Identify these changes. Give another example of a familiar process in which both the chemical and physical changes take place.


Answer :

(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.

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