Indirect spectrophotometric microdetermination of some carboxylic acids and unsaturated organic compounds in aqueous solution

Abstract

Some carboxylic acids (including formic, oxalic and malonic acids) and unsaturated compounds (including crotonic acid, crotonyl chloride and crotonaldehyde) were determined spectrophotometrically by reaction with excess bromine in aqueous solution. The unconsumed bromine was reacted with excess of chloranil and the absorbance of the unconsumed chloranil was measured at 292 nm (pH 9). Microgram amounts of the compounds can be determined with an accuracy of better than ±3% and a relative standard deviation of <3%. The effect of foreign acids on the determination of the carboxylic acids was investigated.