Quantity characterizing the equilibrium of a chemical reaction and defined by an expression of the type \(K_{x}=\underset{\begin{array}{c} \text{B} \end{array}}{\Pi }x_{\text{B}}^{\nu _{\text{B}}}\), where \(\nu _{\text{B}}\) is the @[email protected] of a reactant (negative) or product (positive) for the reaction and \(x\) stands for a quantity which can be the equilibrium value either of pressure, fugacity, @[email protected], amount fraction, molality, @[email protected] or reciprocal @[email protected] defining the pressure based, fugacity based, concentration based, amount fraction based, molality based, @[email protected] based or @[email protected] (then denoted \(K^{\unicode{x26ac}}\)), respectively.
Green Book, 2nd ed., p. 50 [Terms] [Book]