Question

How are physical changes different from chemical changes?​

Answer 1

Difference between Chemical and physical change :

1. Physical change is a temporary change.

A chemical change is a permanent change.

2. A Physical change affects only physical properties i.e. shape, size, etc.

It changes both physical and chemical properties of the substance including its composition.

3. A physical change involves very little to no absorption of energy.

During a chemical reaction, absorption and evolution of energy take place.

4. Physical change is easily reversible i.e original substance can be recovered.

Chemical changes are irreversible i.e. original substance cannot be recovered.

5. Some examples of physical change are freezing of water, melting of wax, boiling of water, etc.

Examples of chemical change are digestion of food, burning of coal, rusting, etc.

Answer 2

Physical changes only change the appearance of a substance, not its chemical composition. Chemical changes cause a substance to change into an entirely substance with a new chemical formula. Chemical changes are also known as chemical reactions.