Question

Substances can undergo physical changes or chemical changes. what is the difference between these two kinds of changes

Answer 1

There are several differences between a physical and chemical change in matter or substances. A physical change in a substance doesn't change what the substance is. In a chemical change where there is a chemical reaction, a new substance is formed and energy is either given off or absorbed.

Answer 2

physical changes are those change which just externally or physically change the state of the object . for example : water boils and evaporates... here the state is just changing from liquid to vapour while the composition is the same.

chemical changes are those which bring about a change in the composition of a substance. for example: burning of paper changes into ash .