1. Elements, compounds and mixtures
Elements – these are substances containing only one type of atom.
For example, sodium is an element and is made up of sodium atoms only.
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2. Compounds – these are substances made up of two or more types of atom
Compounds – these are substances made up of two or more types of atom. These atoms are joined together chemically. For example, carbon dioxide contains carbon and oxygen atoms joined together by chemical bonds.

3. Mixtures – these are not pure substances
Mixtures – these are not pure substances. The compounds and/or elements making them up are not joined chemically.
For example, air is a mixture of gases like oxygen (an element) and carbon dioxide (a compound).
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4. Elements, compounds and mixtures
Classify the following substances as elements, mixtures or compounds.
mixture
compound
element
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