What do you mean Chemical Changes

A chemical change is a change in which one or more new substances are formed with different properties from the original substances. In chemical changes, the composition of the substance changes permanently.

Chemical changes are usually permanent and irreversible. Once the change takes place, it is very difficult or impossible to bring the substance back to its original form.

Examples of Chemical Changes

1. Burning of cooking gas
2. Rusting of iron
3. Ripening of fruits
4. Explosion of crackers

For example, when a cracker burns, it releases heat, light, and smoke. These are new substances formed during the reaction. Therefore, the explosion of a cracker is a chemical change.

Difference Between Physical Change and Chemical Change

Physical Change	Chemical Change
Only physical properties such as shape, size, or state change.	Chemical composition and properties change.
No new substance is formed.	One or more new substances are formed.
Usually reversible.	Usually irreversible.

Examples

Physical changes:

• Conversion of water into ice
• Tearing of paper

Chemical changes:

• Burning of cooking gas
• Ripening of fruits