Question

difference between the following:

a) physical change and chemical change

Answer 1

Physical change is a temporary change and no new substance is formed.
Chemical change is a permanent change and new substance is formed. It cannot be reversed.

Answer 2

In our daily life, we encounter many changes in our surroundings, though we do not notice them, such as souring of milk, rusting of iron, stretching of a rubber band, bread becoming toast, melting of wax, liting of a match, etc. All these changes that take place around us are physical change or chemical change. Physical changes are the changes that change the physical traits of the substance, without making any change in their internal structure.
On the other hand, a chemical change is one that affects the internal structure of the substance, so as to form a new substance. So, take a read of the article to understand the difference between physical change and chemical change.