Pure substance
What Pure substance means in Combined Science GCSE, as defined for AQA.
Definitions of Pure substance
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Reference: AQA
A substance that produces a single spot in every solvent system because it has one fixed composition and one R_f value.
In chemistry, a substance that contains only one substance, so potable water is a mixture.
A single element or compound, not mixed with any other substance.
Topics that use Pure substance
- Chromatography (AQA GCSE)
- Potable water (AQA GCSE)
- Pure substances (AQA GCSE)
Related terms
- Aquifers
- Chlorine
- Chromatogram
- Chromatography
- Comparing measured and known values
- Control variables
- Desalination
- dissolved solids
Using Pure substance in the exam
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