A technique of photometric determination of germanium (IV) in aqueous solution by the molybdenum blue method has been developed. The technique is based on the formation of yellow germanomolybdic acid followed by the blue form restoration with ascorbic acid. The maximum reaction sensitivity has been shown to be at pH 3.5 - 4. The oxalic acid solution has been proposed to mask the harmful influence of the excess of ammonium molybdate and to stabilize the blue form, pH has to be reduced to 1.8. The limit of determination is 1·10-6 mol/l. The technique has been used to determine germanium after organogermanium compound combustion in a bomb calorimeter.
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