Alcohol-in-liquid determination - distilled into oxidant with nitric acid, oxidant remainder determined by back titration

摘要

Determination of alcohol content of liquids e.g. drinks, by distilling from given specimen quantity into excess of oxidant in the presence of nitric acid, and determining the oxidant remainder by back titration. Pref the receiver liquor is chromate dissolved in 20-40% HNO3. and the oxidation at ambient temp. The chromic acid is present at >=0.1-0.3 oxide equivs. per 1. Unreacted chromic acid is produced with KI in which the receiver liquor has been so diluted that the HNO3 present does not oxidise the KI. Distn. proceeds only for 2-5 mins. and without special cooling.