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.

1 (a) Melting of wax during burning of a candle is a physical change.
(b) Burning of wax and thread is a chemical change.
2. The use of LPG also involves two changes:
(a) When the valve is opened, the liquid LPG gets vaporised. This is a physical change.
(b) The burning of LPG is a chemical change because the gas on burning produces carbon dioxide gas and gives light and heat