Combined Science GCSE
R_f value
What R_f value means in Combined Science GCSE, as defined for AQA.
Definitions of R_f value
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Reference: AQA
Calculated using distance moved by substance divided by distance moved by solvent front, measured from the start line, with no units and always between 0 and 1.
A characteristic value linked to the distance travelled by a substance relative to the solvent front.
Topics that use R_f value
- Chromatography (AQA GCSE)
Related terms
- Chromatogram
- Chromatography
- Distribution between phases
- Identification by comparison
- Identification of substances
- Identification using reference values
- Impure substance
- Measurement from a baseline
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