A-Level ChemistryYear 2017Q23
Page 09 23. Using colorimetry, the most appropriate filter for determining the concentration of green nickel ions, Ni2+(aq), in a solution, would be A 390 nm B 490 nm C 540 nm D 680 nm. 24. The diagram shows a thin layer chromatogram for a mixture of amino acids. Distance moved by solvent and amino acids (cm) Solvent front Amino acid S Amino acid R Amino acid Q Amino acid P 9 8 7 6 5 4 3 2 1 0 Which amino acid has an Rf value of approximately 0∙75? A Amino acid S B Amino acid R C Amino acid Q D Amino acid P [Turn over
Paper Source:NAH_Chemistry_all_2017.pdf
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Exam Specification Info
This question is part of the UK A-Level Chemistry syllabus. In the actual exam, structured questions typically require linking specific keywords to gain full marks. Applaa helps you drill these topics.
Syllabus levelAdvanced Level (A-Level)
SubjectChemistry
Official MarksVariable (2–6 marks)