CBSE Class 12-science Answered

a dissociation constant is a specific type of equilibrium constant that measures the propensity of a larger object to separate (dissociate) reversibly into smaller components,

The dissociation constant is usually denoted K_d and is the inverse of the affinity constant. In the special case of salts, the dissociation constant can also be called an ionization constant.

For a general reaction

in which a complex A_xB_y breaks down into x A subunits and y B subunits, the dissociation constant is defined

where [A], [B], and [A_xB_y] are the concentrations of A, B, and the complex A_xB_y, respectively.