Preparation, Tests and Analysis of Mn III Compounds

Generally manganese (III) complexes are prepared by oxidising a manganese (II) compound with permanganate in presence of the ligand. The conditions depend on the stability of the product and the reactivity of the reagents. 

A useful method of analysis is to dissolve a known mass of the compound in a known excess of standardised ascorbic acid solution, back-titrating the excess with standardised Mn(III) sulphate solution or other oxidants. Alternatively, a known mass of the compound is treated with an excess of iodide solution, titrating the liberated iodine with standardised thiosulphate. 

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