Question

what does the equilibrium expression represent? the ratio of product to reactant concentrations at the beginning of a reaction the ratio of reactant to product concentrations at the beginning of the reaction the ratio of reactant to product concentrations at equilibrium the ratio of product to reactant concentrations at equilibrium

Explanation:

The equilibrium expression is defined as the ratio of the concentrations of products to reactants, each raised to their stoichiometric coefficients, at equilibrium. It does not represent initial concentrations at the start of a reaction.

Answer:

The ratio of product to reactant concentrations at equilibrium