An environmental scientist analyses pollutants in river water using thin layer chromatography. A component moves 8.4 cm while the solvent front moves 10.5 cm. What is the Rf value of this component?

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Question

An environmental scientist analyses pollutants in river water using thin layer chromatography. A component moves 8.4 cm while the solvent front moves 10.5 cm. What is the Rf value of this component?

Accepted Answer

0.80 — 80. Award 1 mark for correct calculation. Rf = 8.4 ÷ 10.5 = 0.80. A is incorrect (incorrect division). C is incorrect because it inverts the calculation (10.5 ÷ 8.4). D is incorrect because it multiplies the values instead of dividing.

Answer

1.25

Answer

0.80

Answer

0.75

Answer

88.2

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