• V TEJESWARA RAO
• P LAKSHMI KISHORE
• G.Nageswara Rao

A computer assisted pH-metric investigation has been carried out on the speciation of complexes of Co(II), Ni(II) and Cu(II) with MSA. The titrations were performed in the presence of different relative concentrations with sodium hydroxide in varying concentrations (0–60% v/v) of acetonitrile–water mixtures and DMF-water mixtures at an ionic strength of 0.16 mol L-1 and at a temperature of 303.0 K. Stability constants of the binary complexes were refined using MINIQUAD75. The best-fit chemical models were selected based on statistical parameters like crystallographic R factor and sum of the squares of residuals in mass-balance equations. The models for binary complex systems contain the chemical species ML, ML2, MLH, ML2H and ML2H2 for Co(II), Ni(II) and Cu(II) in acetonitrile-water and DMF-water mixtures. The trend in the variation of stability constants with change in the mole fraction of the medium was explained based on electrostatic and non-electrostatic forces. Distribution of the species with pH at different compositions of acetonitrile-water and DMF-water mixtures was also presented.

MSA, Acetonitrile, DMF, MINIQUAD75, stability constants, best-fit chemical model

"Chemical Speciation Of Binary Complexes Of Co(II), Cu(II) And Ni(II) With Mercaptosuccinic Acid In Acetonitrile-Water And DMF-Water Mixtures", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.6, Issue 1, page no.607-616, January-2019, Available :http://www.jetir.org/papers/JETIR1901578.pdf

"Chemical Speciation Of Binary Complexes Of Co(II), Cu(II) And Ni(II) With Mercaptosuccinic Acid In Acetonitrile-Water And DMF-Water Mixtures", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.6, Issue 1, page no. pp607-616, January-2019, Available at : http://www.jetir.org/papers/JETIR1901578.pdf