laws of distribution

in precipitation
Also contains definition of: logarithmic distribution coefficient in precipitation
During the formation of a mixed crystal from a solution containing two components 'A' and 'B', the latter may be distributed according to the equation \[K_{\text{A},\text{B}}=\frac{b\ (a_{0}- a)}{a\ (b_{0}- b)}\] In this homogeneous distribution, a0 and b0 are the respective concentrations in the solution before crystallization and a and b are the respective concentrations in the solution after crystallization. KA,B is usually called the separation factor. The term homogeneous distribution coefficient is not recommended. Alternatively the distribution of the micro-component may follow the equation of Doerner and Hoskins \[\ln (\frac{a_{0}}{a}) = \lambda \ \ln (\frac{b_{0}}{b})\] (logarithmic distribution) where λ is usually called the logarithmic distribution coefficient, the meaning of the other symbols remaining the same. Exactly homogeneous or logarithmic distributions are extreme cases and very seldom encountered.
Orange Book, 2nd ed., p. 85 (