Jämviktskonstantens

Jämviktskonstanten, often denoted as K, is a fundamental concept in chemical kinetics and thermodynamics. It quantifies the ratio of products to reactants at chemical equilibrium for a reversible reaction. At equilibrium, the rate of the forward reaction equals the rate of the reverse reaction, and the concentrations of all species remain constant. The value of the equilibrium constant is temperature-dependent and provides insight into the extent to which a reaction proceeds. A large K value indicates that the equilibrium lies far to the right, favoring the formation of products. Conversely, a small K value signifies that the equilibrium favors reactants.

For a general reversible reaction aA + bB <=> cC + dD, where a, b, c, and d are stoichiometric coefficients, the equilibrium constant expression is given by K = ([C]^c * [D]^d) / ([A]^a * [B]^b). Here, the square brackets denote the molar concentrations of the respective species at equilibrium. This expression applies to homogeneous reactions where all reactants and products are in the same phase, typically aqueous or gaseous. For heterogeneous reactions, where different phases are involved, the concentrations of pure solids and liquids are omitted from the expression as they are considered constant. The equilibrium constant is a powerful tool for predicting the direction a reaction will shift to reach equilibrium and for calculating equilibrium concentrations.