Combined Science GCSE
Identification by comparison
What Identification by comparison means in Combined Science GCSE, as defined for AQA.
Definition of Identification by comparison
Check what you remember
Read the wording for your board, then hide it and explain Identification by comparison in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: AQA
Identification requires running a known pure sample under the same conditions and comparing R_f values or spot positions.
Topics that use Identification by comparison
- Chromatography (AQA GCSE)
Related terms
- Chromatogram
- Chromatography
- Distribution between phases
- Identification of substances
- Identification using reference values
- Impure substance
- Measurement from a baseline
- Pure substance
Using Identification by comparison in the exam
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