During paper chromatography of a blue food dye, the solvent front moved 8.20 cm and dye component A moved 5.10 cm.
Calculate the Rf R_f\,Rf value for dye component A. Give your answer to two significant figures.
107 exam-style questions on Edexcel GCSE Chemistry 3.2 Methods of separating and purifying substances, covering 3.2.1 Pure substances and mixtures, 3.2.2 Techniques for separating mixtures, 3.2.3 Paper chromatography and Rf values, and 3.2.4 Making water potable. Each one has a worked solution and a mark scheme showing where the marks go.