Precise coulometric determination of acids in cells without liquid junction. Part I. Introduction and instrumentation

Abstract

The requirements of high-precision amperostatic coulometry in the absolute mode are summarised, and the apparatus and instruments used described. Three constant-current sources are appraised: a 10-mA operational amplifier circuit, a commercial coulometric titrimeter and a commercial analogue computer high-current source. The first and last have shown noise and drift levels that are acceptable in high-precision work.