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Chemistry · Paper 2 · Foundation + Higher · C8

Pure substances and mixtures

Key ideas1 of 3

Pure has a precise meaning

In chemistry, a pure substance is one element or one compound, not mixed with other substances. Pure oxygen is an element. Pure water is a compound. Both can be pure.

Particle samples: A contains identical red atoms; B identical bonded red-blue pairs; C contains both red atoms and red-blue pairs. Colours represent different elements.

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Foundation + Higher · C8. All C8 lessons are shared by Foundation and Higher Tier.

AQA Combined Science Trilogy 8464 · 5.8.1.1. Original notes, questions and diagrams. Models are simplified, not to scale; illustrative data are labelled.