Serine as ligand towards copper(II) and lead(II).

The beaviour of serine as a ligand towards copper(II) and Lead(II) has been studied by means of electromotive force measurements at 25°C and in 3.00M (Na)ClO4. Experimental dataobtained from the measurements of the cell: R.E./Solution S / G.E. and respectively of cells: Cu(Hg)/Solution S/R.E. ; Pb(Hg)/Solution S/R.E. were explained by assuming the formation of following species: CuL (log B1,0,1 =8.55+_0.05); CuHL (log B1,1,1 =10.90 +_ 0.10) and CuL2 (logB1,0,2 =16.02 +_ 0.06) for the system copper(II)-serine and PbL (log B1,0,1 =5.28+_0.04); PbHL (log B1,1,1 =10.87+_0.05); PbL2 (log B1,0,2 =8.45+_0.07); PbHL2 (logB1,1,2 =15.5+_0.1); PbH2L2 (log B1,2,2 =21.2 +_ 0.1) for the system lead(II)-serine. The protonation constants of serine were determinedin the present experimental conditions by employing a hydrogen electrode. Values obtained were: logK1 =9.72+_0.03 and log K1K2 = 12.20 +_ 0.05.