Interaction of phenylarsonic acid derivatives with Group IIA metal ions

Department of Chemistry, Punjab Agricultural University. Ludhiana-148 001, India

Department of Chemistry. SUET, Longowal, Sangrur-148 106. India

E-mail : d_sud@rediff.com Fax: 95167-3280057

Manuscript received 7 November 2001. revised 24 September 2002. accepted 12 December 2002

The proton-ligand stability constants and stability constants of complexes of Group IIA metal ions with o-amino- and ohydroxyphenylarsonic acids have been determined potentiometrically at 30º at ionic strengths of 0.05, 0.10, 0.20 M and also at 20º and 40º at an ionic strength of 0.05 M. The stability order for 1 : 1 complexes is Ca^II < Sr^II < Ba^II . In case of Mg^II and Be^II complexes, precipitation occurred early during titration. The thermodynamic parameters have been evaluated.