Chemical Properties
colourless crystals or white crystalline powder
Uses
Powerful oxidizer in acid solution, oxidizing manganese Compounds to permanganate; used for this purpose in analytical chemistry (colorimetric estimation of Mn), also for the oxidation of some organic Compounds.
Hazard
Fire risk in contact with organic materials,
strong oxidizing agent. Strong irritant to tissue.
Physical properties
Colorless tetragonal crystals; density 3.618 g/cm3; melts at 582°C; slightly soluble in water at ordinary temperatures, 0.42 g/100mL at 20°C; moderately soluble in hot water, 4.4 g/100mL at 80°C.
Preparation
Potassium periodate can be prepared by oxidation of potassium iodate with a powerful oxidizing agent such as potassium permanganate, chlorine or bromine in basic solution:
IO3ˉ+ Cl2+ 2OHˉ→IO4ˉ+ 2Clˉ+ H2O
Also, the salt may be prepared by electrolysis.
Production Methods
Potassium periodate, KlO4, white solid, formed by electrolysis of potassium iodate under proper conditions.
Purification Methods
Crystallise it from distilled water. Its solubility in H2O is 0.2% at 0o, 0.4% at 20o, 4.4% at 80o. and 7.9% at 100o. [Hill Inorg Synth I 171 1939, Schmeisser in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol I p 325 1963.]
General Description
Potassium (meta)periodate exhibits strong oxidizing properties in acidic medium.
