Question

explain the theory of partition coefficient

Answer 1

A partition-coefficient (P) or distribution-coefficient (D) is the ratio of concentrations of a compound in a mixture of two immisciblephases at equilibrium. This ratio is therefore a measure of the difference in solubility of the compound in these two phases.

It has a broad application side. A drug's distribution coefficient strongly affects how easily the drug can reach its intended target in the body. In environmental studies the hydrophobicity of a compound can give scientists an indication of how easily a compound might be taken up in groundwater to pollute waterways, and its toxicity to animals and aquatic life.

The concept of partition function comes from Henry's law which state m/p = k i.e. mass dissolved varies proportionally with pressure. Clearly it states that the miscibility of a solute depends on various factors.

So when we add several components their solubility gets influenced by the other one which brings the concept of partition function.

If you want to know more, I suggest you to read this arcile published in ACS. DOI no of the review is 10.1021/cr60274a001.