Question

Classify each of the following as a physical or chemical change. Give reasons.

a. Drying of a shirt in the sun.

b. Rising of hot air over a radiator.

c. Burning of kerosene in a lantern.

d. Change in the colour of black tea on adding lemon juice in it.

Answer 1

a is physical , b is chemical ,c is chemical and d is also chemical

Answer 2

a) It's an example of physical change as reaction takes place and water evaporates making the cloth dry.
b) It is an example of physical change as the air over the radiator gets hot and rises.
c) It is a chemical change as Kerosene reacts with oxygen to burn and give off light. A chemical reaction occurs and new product is formed.
d) It is a chemical change as the colour change represents the formation of a new product.