Equilibrium Constant

Equilibrium constant (K) for a chemical reaction can be described as the ratio between concentrations of the products to the concentrations of the reactants. It is used to determine chemical behaviour of the reaction.

The rate constants are constant at a given temperature. The ratio of the forward reaction rate constant to the backward reaction rate constants should remain same, and this is referred to as the equilibrium constant (K).

The general form of the equilibrium constant expression for a reaction is:

[Tex]K= \frac{[C]^c. [D]^d} {[A]^a. [B]^b}[/Tex]​

Where:

• [A], [B], [C], and [D] are the molar concentrations of the reactants and products at equilibrium,
• a, b, c, and d are the coefficients of the reactants and products in the balanced chemical equation.

Units of Equilibrium Constant

Equilibrium constant is a dimensionless quantity because it expresses the ratio of product concentrations to the reactant concentrations, each raised to the power of its stoichiometric coefficient. Consequently, when the concentrations (or partial pressures) are divided, the units of the equilibrium constant cancel out making it a dimensionless quantity.

Check, Applications of Equilibrium Constants

Heterogeneous Equilibrium is a state of equilibrium in a system where multiple phases coexist. This usually refers to substances existing simultaneously in multiple physical states, such as solid, liquid, and gas.

This article covers the basic ideas of heterogeneous equilibrium, its examples, and reactions along with a few problems based on the concept.