Question

why tearing of paper is a physical change where where as burning of candle is a chemical change

Answer 1

Yes.. Because when u tear a paper there is no change in chemical composition of the paper. And when u burn a candle heat energy and light energy r involved which means they r chemical change...

Answer 2

Tearing of paper is one of those rare physical changes which is practically irreversible. Because when you tear a piece of paper and use the best adhesive in the world to join , it does not attain its original shape. But , as the change does not change the composition of the substance and does not form a new substance , it is considered as physical change.

Burning of candle is a chemical change because in this , the wax along with oxygen react chemically to form new substances such as carbon dioxide etc.. This change is exothermic as it releases heat. And as the candle burns the wax also melts which cannot be brought back.Hence,it is irreversible and forms a new substance.