Physical & Chemical Properties/Changes

A physical change is a change that alters the physical properties of a substance but does not change 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 a chemical reaction and cannot be undone. Examples include burning, rusting, and digestion.

An indicator of a chemical change can include a change in temperature without an external heat source, the formation of gas, or a color change.

Melting a chocolate bar is a physical change.

The physical properties of a substance may change, but the substance itself remains the same.

An example of a physical change is tearing a piece of paper.

An example of a chemical change is iron rusting.

It means that the substance changes its form or appearance but not its chemical identity.

Physical changes do not create new substances, while chemical changes do.

An example of a chemical change that produces gas is the reaction between baking soda and vinegar.