1 Esters can be used as solvents in chromatography. The following shows a chromatogram of plant acids. solvent front the cross represents the centre of the spot baseline sample 1 sample An ester was used as the solvent and the chromatogram was sprayed with bromothymol blue. (1) Suggest why it was necessary to spray the chromatogram. (ii) Explain what is meant by the Rf value of a sample. (iii) Calculate the Rf values of the two samples and use the data in the table to identify the plant acids.

1 Esters can be used as solvents in chromatography. The following shows a chromatogram of plant acids. solvent front the cross represents the centre of the spot baseline sample 1 sample An ester was used as the solvent and the chromatogram was sprayed with bromothymol blue. (1) Suggest why it was necessary to spray the chromatogram. (ii) Explain what is meant by the Rf value of a sample. (iii) Calculate the Rf values of the two samples and use the data in the table to identify the plant acids.

EBK A SMALL SCALE APPROACH TO ORGANIC L

4th Edition

ISBN:9781305446021

Author:Lampman

Publisher:Lampman

Chapter91: Gas Chromatography

Section: Chapter Questions

Problem 1P

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