P 2377 (OTTO) Potassium periodate, GR 99%+ Cas 7790-21-8 - used as an oxidizing agent in organic synthesis and an analytical reagent for the determination of potassium and cerium. It is also used in colorimetric estimation of manganese. It reacts with ammonium cerium(IV) nitrate to prepare tris[trinitratocerium(IV)] paraperiodate which finds application as an oxidant.