How does a decrease in pressure affect the equilibrium position of a reaction with more moles of gas on the reactant side?

A decrease in pressure will shift the equilibrium position towards the side with more moles of gas. This is because the system seeks to increase the pressure by favoring the formation of more gas molecules, thus increasing the concentration of reactants. This answer is anchored to Equilibrium and Le Chatelier's principle.

A decrease in pressure will shift the equilibrium position towards the side with more moles of gas. This is because the system seeks to increase the pressure by favoring the formation of more gas molecules, thus increasing the concentration of reactants. is the best answer because it directly supports the AQA A-Level Chemistry objective to use Le Chatelier's principle to predict the effect of pressure changes. This reasoning is anchored to Equilibrium and Le Chatelier's principle in Chemical equilibria, Le Chatelier's principle and Kc, and it separates Le Chatelier from similar A-Level ideas rather than relying on a vague recall statement. Other options are weaker if they use the wrong evidence, calculation, mechanism, observation, unit, or conclusion for this subtopic.