In chemistry and biochemistry, a dissociation constant is a specific type of equilibrium constant that refers to the extent to which a complexes, molecule, or salt separates or splits into smaller molecules, ions, or radicals in a reversible manner. The dissociation constant is represented by the symbol K_d.

Given the reaction

A_xB_y <=> xA + yB

It is given by the expression

K_d = [A]^x×[B]^y×[A_xB_y]^-1

Where [A], [B], and [A_xB_y] indicate the concentrations of A, B, and A_xB_y, respectively.

See also

• Receptor (biochemistry)
• Dissociation (chemistry)
• Equilibrium Constant