PHYSICO-CHEMICAL STUDY OF THE COMPLEX FORMATION OF BERYLLIUM IONS WITH ORGANIC LIGANDS. PART IV. WITH MALONIC ACID AND ITS DERIVATIVES

Beryllium sulfate was found to form 1: 1 complexes with malonic acid, sodium malonate, and diethyl malonate. The complex formation was studied by the electrical conductance data, potentiometric data, and spectrophotometric data in the ultraviolet region with the help of Job's continuous variation method. The values of the dissociation contants thus obtained are 9.55 x 10/sup -4/ for malonic acid, 9.24 x 10/sup -4/ for sodiom malonate, and 9.81 x 10/sup -4/ for diethyl malonate at 28 deg C. A precise structure was attributed to the complex formed and justified both from theoretical considerations and from practical data. As can be seen from a comparison of the values of the dissociation constants, the complex with sodium malonate is slightly more stable than the complex formed with malonic acid and the complex formed with the ethyl substituted malonic acid is slightly less stable than that formed with malonic acid, presumably due to the weakening of the electron donating properties of the acid. (auth)