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

.

In this homogeneous distribution, and
are the respective concentrations in the solution before crystallization and
and
are the respective concentrations in the solution after crystallization.
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
(logarithmic distribution) where
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.
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