Caffeine Quantification Via High-Precision Coulometric Titration

High Precision Coulometric Titration of Uranium

An improved method for the coulometric assay of uranium and uranium oxide has been developed based on the electrogeneration of Tif II in H2SO,, using Fe(lI) as a catalyst. The endpoint is determined amperometrically. Hydrogen peroxide is used as the oxidant in the dissolution of the uranium to avoid interferences from nitrate. The precision of the method as indicated by the standard deviation o...

A Coulometric-Titration Coulometer

A highly precise coulometer is described which permits time integration of currents totaling 100 coulombs or more with a precision of about 1 part in 100,000. The current to be integrated oxidizes hydroquinone in an electrolysis cell, producing quinone and acid. The quinone is t hen reduced by constant-current coulometric titration, the end point being indicated by hydrogen-ion concentration me...

Coulometric Titration with Electrogenerated Tin(II). Titration of Platinum(IV)

Precise Coulometric Titration of Acids and Bases

Apparatus and techniques a re dc~cribed for t he t itration of ac ids a nd. bases by constantcurrent coulometry. The precision nnd accuraey of t he method aI~e JndLcated by tl traLlons of benzoic acid, potass ium acid pMhalate, adLpiC aCld, hydroc~lo l'l c aCid, ~nd sod ium eal'bonate. Standard deviations of ± 0.003 p er cent have been obtaIned which LndlCatp. that the reliabi li ty of the meth...

Coulometric titration of urea with electrogenerated hypobromite.

A definitive method is described for the indirect assay of several tens of milligrams of urea by coulometric titration. Urea was decomposed in concentrated sulfuric acid using a Kjeldahl flask. Subsequently, the formed ammonium ion was titrated with electrogenerated hypobromite ion in a sodium bromide-sodium tetraborate medium of pH 8.6, with amperometric end-point detection. Parameters affecti...