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A-LevelChemistryEquilibriaMay/June 2022Paper 1 Q141 Mark

Hydrogen and iodine can react reversibly to produce hydrogen iodide. The equation is shown. H₂(g) + I₂(g) ⇌ 2HI(g) 4.00 mol of hydrogen gas and X mol of iodine vapour are mixed in a sealed container of volume 1.00 dm³ at a temperature of 460 K. The system is allowed to reach equilibrium. The equilibrium mixture contains 2.00 mol of hydrogen iodide. The equilibrium constant, K_c, for the reaction at 460 K is 4.0. What is the value of X?

A0.50 mol
B1.17 mol
C1.33 mol
D2.50 mol

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The correct answer is C. This question tests the candidate's understanding of equilibria within the Chemistrysyllabus. The examiner's mark scheme requires...

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About This A-Level Chemistry Question

This multiple-choice question appeared in the Cambridge A-Level Chemistry (9701) May/June 2022 examination, Paper 1 Variant 2. It tests the topic of Equilibria and is worth 1 mark.

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