A-LevelChemistryEquilibria9701/12 · May/June 2020 · Q111 Mark

PCl5 decomposes as shown. PCl5(g) ⇌ PCl3(g) + Cl2(g) 1.0 mol of PCl5(g), 1.0 mol of PCl3(g) and 1.0 mol of Cl2(g) are placed in a container of volume 1 dm³ at 250 °C and allowed to reach equilibrium. At this temperature, the equilibrium mixture contains 1.8 moles of PCl3. What is the value of Kc at 250 °C?

B1.8

D16.2

✓ Correct answer

D: 16.2

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Topic: Equilibria, A-Level Chemistry (syllabus 9701). Multiple choice, 1 mark.
Source: A-Level Chemistry, May/June 2020 Paper 1 Variant 2, question 11.

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