Difference between revisions of "Retention Factor"
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d<sub>s</sub> = distance moved by the [[solvent]] | d<sub>s</sub> = distance moved by the [[solvent]] | ||
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| + | ===References=== | ||
| + | ====AQA==== | ||
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| + | :[https://www.amazon.co.uk/gp/product/0198359381/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359381&linkCode=as2&tag=nrjc-21&linkId=47c8d1ae58d8b3a5e2094cd447154558 ''Retention factors, page 183, GCSE Chemistry; Third Edition, Oxford University Press, AQA ''] | ||
Latest revision as of 17:16, 12 November 2019
Contents
Key Stage 4
Meaning
The Retention Factor is a ratio of how far a chemical moves along the paper compared to how far the solvent moves along the paper in a chromatography experiment.
About Retention Factors
- Each chemical has a Retention Factor (Rf number).
- The larger the Retention Factor the greater the force of attraction experienced by the chemical to the paper. The chemical is 'retained' in place.
- Rf numbers are unique to each chemical and can be used to separate and identify the chemical.
Equation
Retention Factor = (distance moved by chemical)/(distance moved by solvent)
\(R_f = \frac{d_c}{d_s}\)
Where:
Rf = Retention Factor
dc = distance moved by the chemical
ds = distance moved by the solvent