Stability Constants of Orthocarboxyphenyl di(p-tolyl) arsine Complexes

Department of Chemistry and Biochemistry, Punjab Agricultural University, Ludhiana

Manuscript received 30 August 1974; accepted 2 May 1975

The proton-ligand stability constant of Orthocarboxyphenyl di(p-tolyl) arsine and the step­wise stability constants of its complexes with Ni(II), Cu(II), Hg(II), UO₂ (II), La(III) and Ce(III) have been determined in ethanol-water (70 : 30, v/v) system by potentiometric method at 30° and 40° at μ = 0.1 M. The values of log K₁^H are 6.38 at 30° and 6.26 at 40°. The order of stability constants for 1 : 1 and 1:2 complexes has been found to be Hg(II) > UO₂ (II) > Cu(II) > whereas La(III) > Ce(III) is the order for 1 : 1 complexes.