1. Two methods of titrating chloride with Ag+ ion using the potentiometric end-point are described.
2. The first method is conventional in that silver nitrate is added from a burette. It deals with volumes down to 0.2µl. and can measure 1µg. of chloride with an error of < ± 1% (standard deviation).
3. According to the second method Ag+ ion is added by passing a current through a silver electrode in series with a condenser. The charge developed on the condenser is a measure of the amount of chloride titrated. This method deals with volumes down to 0.5 x 10-3µl. and can measure 10-4µg. of chloride with an error of < ± 1% (standard deviation).
4. As far as is known these methods are not susceptible to interference from other substances likely to be present in biological fluids.