You have been asked to buy a woollen sweater from the market. How will you check its purity
We can test the purity of the woollen sweater by burning it. Take about 10 cm long thread (spare one). Hold it with the help of a tong and burn its one end. If the fibre smells like burning hair, it is wool but if . the fibre smells like chemicals or burning plastic, it is artificial wool. On blowing out of the flame touch the end of the fibre. If the end turn to dust on touching then it is pure wool but if the end has melted and turned hard, then it is not pure wool.
