An analyst investigated a batch of orange food dye using paper chromatography.
The orange dye formulation consists of 65%65\%65% yellow dye and 35%35\%35% red dye by mass. Determine the simplest whole-number ratio of yellow dye : red dye in this formulation.
On the developed chromatogram, the analyst obtained the following measurements:
Calculate the RfR_{\text{f}}Rf value of the yellow dye using the equation:
Rf=distance moved by dyedistance moved by solvent R_{\text{f}} = \frac{\text{distance moved by dye}}{\text{distance moved by solvent}} Rf=distance moved by solventdistance moved by dyeUnder identical experimental conditions, if the analyst tested a different formulation of orange dye containing 45%45\%45% yellow dye and 55%55\%55% red dye, state what would happen to the RfR_{\text{f}}Rf value of the yellow dye.
28 exam-style questions on AQA GCSE Chemistry 8.1 Purity, formulations and chromatography, covering 8.1.1 Pure substances, 8.1.2 Formulations, and 8.1.3 Chromatography. Each one has a worked solution and a mark scheme showing where the marks go.