Practice and Revision - Elements, Compounds and Mixtures

Core concept

Elements, like oxygen or gold, are pure substances that cannot be broken down into simpler substances by chemical means.

How it works

Compounds, like water (H₂O) or salt (NaCl), form when two or more elements combine chemically in fixed proportions.

Why it matters

Mixtures, like air or salad, combine substances physically without chemical bonding, so components keep their individual properties.

Key detail

Mixtures can be separated by physical methods like filtration or evaporation, while compounds require chemical reactions to separate.