Description:
<jats:title>Abstract</jats:title><jats:p>Because of the formation of KI<jats:sub>3</jats:sub>, potassium iodide increases the extraction rate of iodine from petroleum ether into water. Nernst's constant of the distribution of iodine in the system water/petroleum ether (KN = 34.1 ± 4.6) and the equilibrium constant of the formation of KI<jats:sub>3</jats:sub> from iodine and potasium (K<jats:sub>K</jats:sub> = 820 ± 203 1 · mol<jats:sup>−1</jats:sup>) are determined by titration of I<jats:sub>2</jats:sub> or KI<jats:sub>3</jats:sub> in the separated organic and aqueous layers with thiosulfate standard solution. Aspects of environmental protection are an integral part of the experiments,e.g. iodine and petroleum ether are recycled.</jats:p>