Tensammetric studies of thiourea and its derivatives

Adsorption of thiourea and some of its derivatives at the mercurysolution interface has been studied by the tensammetric technique. It has been found that adsorption of thiourea increased the differential capacity rather than decreasing it. However the adsorption of S-methyl derivative of thiourea decreased the differential capacity. The N-substituted derivatives depressed the tensammetric curve of the supporting electrolyte to a greater extent than the N, N¹-substituted derivatives. The different behaviours of thiourea and its derivatives are discussed.