If more reactants are added to a chemical reaction already at equilibrium (thus disturbing it),
a reactant-to-product shift is required to restore an equilibrium condition.

Question

Quizplus · Accepted Answer

According to Le Chatelier's principle, when a stress is applied to a system at equilibrium, the system will shift in a way that counteracts the stress. In this case, adding more reactants is a stress on the equilibrium system, so it will shift towards the products to counteract the stress and restore equilibrium. Therefore, a reactant-to-product shift is required.

If More Reactants Are Added to a Chemical Reaction Already