Chemistry GCSE
Comparison with known values
What Comparison with known values means in Chemistry GCSE, as defined for AQA.
Definition of Comparison with known values
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Reference: AQA
Checking a measured melting or boiling point against the known value for the expected pure substance, where a close match to the sharp known value indicates purity.
Topics that use Comparison with known values
- Pure substances (AQA GCSE)
Related terms
- Context in scientific language
- Effect of impurities on physical properties
- Everyday versus chemical meaning
- Evidence-based conclusions
- Melting and boiling point data
- Melting and boiling points
- Mixture
- Mixtures versus pure substances
Using Comparison with known values in the exam
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