Two spots on a chromatogram have Rf values of 0·3 and 0·8 in the same solvent. What can be concluded?

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Question

Two spots on a chromatogram have Rf values of 0·3 and 0·8 in the same solvent. What can be concluded?

Accepted Answer

They are different substances, because the same substance in the same solvent gives the same Rf — Award 1 mark. Rf is a reproducible property under fixed conditions, which is why reference values can be used for identification, provided the same solvent is used.

Answer

They must both be pure elements

Answer

They are the same substance measured twice

Answer

They are different substances, because the same substance in the same solvent gives the same Rf

Answer

The chromatogram has been run incorrectly

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