Chemical and Physical Changes

A physical change is a change that affects one or more physical properties of a substance without altering its chemical composition. Examples include melting, freezing, and dissolving.

A chemical change is a change that results in the formation of new chemical substances. It involves making or breaking bonds between atoms. Examples include rusting, burning, and cooking.

Freezing chocolate covered bananas is a physical change.

When sugar dissolves in water, a physical change occurs.

Cracking an egg is a physical change.

An example of a chemical change is rusting of a bicycle.

Burning sugar is an example of a chemical change.

Indicators of a chemical change include color change, temperature change, gas production, and the formation of a precipitate.

A physical change does not alter the chemical composition of a substance, while a chemical change results in new substances being formed.

Many physical changes can be reversed, such as freezing and melting, but some may not be easily reversible.