The 3M Potassium Chloride Solution is an aqueous reagent that consists of potassium and chloride ions. When dissolved in water, these ions help the balance of electrolytes in living organisms and play a role in metabolic processes. When dissociated, KCl acts as a cofactor in enzymatic reactions related to protein synthesis and function. KCl Solution also enables biological assays, and is often used in the preparation of buffer solutions for polymerase chain reactions, DNA and RNA isolation.