Abstract
Lithium, sodium, potassium, strontium and barium were determined by the double-cell coulometry.
The authors used a new double-cell in which an electrolyte was separated into upper and lower cells by mercury layer laid on cation-exchange membrane. The sample was deposited to form the amalgam at the upper face of mercury and dissoluted into the lower cell.
The coulometric measurement was performed by an integration of the dissolution current of the amalgam under the controlled potential.
The current efficiency of potassium was about 97%, and it's standard deviation was less than one %. The time for a determination was 20 minutes.
