Lesson 5 of 5

Elements, compounds and mixtures

Goal: Use particle diagrams to tell elements, compounds and mixtures apart.

Puzzles for this lesson

Word search0 of 8 foundCrossword0 of 41 letters

In these particle diagrams, each circle is an atom. Circles that match are atoms of the same element. Circles that overlap are atoms joined together.

ElementCompoundMixture

Here there are two elements. One has big atoms. The other has small atoms.

  • Element: only one type of atom. The atoms may be single, or joined in molecules.
  • Compound: atoms of different elements joined together. Every particle of the compound is the same.
  • Mixture: two or more kinds of particle, not joined to each other. A mixture can hold elements, compounds or both.
A glass of orange juice next to a gold ring
Pure or mixed? An element or a compound on its own is a pure substance. The gold in the ring is an element. The orange juice is a mixture of water and many other compounds.

Your turn

This lesson’s activity starts here in a moment.

Check yourself

Knowledge organiser

This lesson on one page. Tap it to make it bigger.

Key words in this lesson

Atom The smallest particle of an element that can exist

Element A substance made of only one type of atom

Compound Two or more elements chemically joined together

Molecule A group of two or more atoms joined together

Mixture Two or more substances mixed together, not joined

Particle diagram A drawing that shows each atom as a circle

Pure substance A single element or a single compound, with nothing mixed in

For teachers: AQA 3.5.4 · Pearson Edexcel 12.1, 14.1 · Cambridge 7Cm.04, 7Cm.07