Biology A-Level
Rf values and comparison with standards
What Rf values and comparison with standards means in Biology A-Level, as defined for OCR.
Definition of Rf values and comparison with standards
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Reference: OCR
The distance travelled by the compound divided by the distance travelled by the solvent front, compared with known standards to identify a compound.
Topics that use Rf values and comparison with standards
- Use of apparatus and techniques (OCR A-Level)
Related terms
- Accuracy of observation transferred to paper
- Accurate reading of scales and menisci
- Annotation as recorded evidence
- Apparatus selection
- Calibration of the eyepiece graticule
- Clarity and convention in biological drawing
- Colorimetry and calibration
- Computer modelling
Using Rf values and comparison with standards in the exam
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