If K < 1, which statement is correct?

If K < 1, which statement is correct?

• A. The reaction rate is zero
• B. Products are favored
• C. Both sides are equally favored
• D. Reactants are favored

Answer: (D)

When a reaction is at equilibrium, the equilibrium constant K tells you how the concentrations of products compare to reactants. If K is less than one, the ratio of product concentrations to reactant concentrations is small, so the system favors the left-hand side and there are more reactants than products at equilibrium. This doesn’t mean the reaction stops—the forward and reverse rates are equal at equilibrium—but the balance tips toward reactants under these conditions. If K were greater than one, products would be favored instead. Temperature can shift K, so changing conditions could change which side is favored.

When a reaction is at equilibrium, the equilibrium constant K tells you how the concentrations of products compare to reactants. If K is less than one, the ratio of product concentrations to reactant concentrations is small, so the system favors the left-hand side and there are more reactants than products at equilibrium. This doesn’t mean the reaction stops—the forward and reverse rates are equal at equilibrium—but the balance tips toward reactants under these conditions. If K were greater than one, products would be favored instead. Temperature can shift K, so changing conditions could change which side is favored.