O-LevelChemistryRates of Reaction5070/11 · May/June 2025 · Q181 Mark

In a closed flask, gases Q and R reach a dynamic equilibrium. Q(g) ⇌ 2R(g) ∆H is positive Which change will move the equilibrium to the right?

Aadding a catalyst

Bdecreasing the temperature

Cincreasing the pressure

Dincreasing the volume of the flask

✓ Correct answer

D: increasing the volume of the flask

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Topic: Rates of Reaction, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source: O-Level Chemistry, May/June 2025 Paper 1 Variant 1, question 18.

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