The kinetics of the reaction between magnesium and EBT

✍ Scribed by Ruth Koren; Berta Perlmutter-Hayman; Ruth Shinar

• Publisher: John Wiley and Sons
• Year: 1974
• Tongue: English
• Weight: 746 KB
• Volume: 6
• Category: Article
• ISSN: 0538-8066
• DOI: 10.1002/kin.550060105

✦ Synopsis

Abstract

The kinetics of the reaction between Mg^2+^ and Eriochrome‐Black‐T (EBT) has been investigated in the pH range between 7.05 and 9.0, in the presence of 12% ethanol. The reaction is found to consist of two parallel paths, one involving the tervalent unprotonated ligand, and one its monoprotonated form. The rate constant for the unprotonated ligand has a “normal” value, whereas that for the protonated form is much lower. The numerical value of the rate constant for the unprotonated ligand obtained from results at a magnesium concentration of 10^−3^M and a pH up to 9.0 is, however, inconsistent with that obtained from results at [Mg^2+^] = (1 to 4) × 10^−3^M and pH up to 8.1. This can be explained, at least partially, if we assume the intermediate MgHD to lose its proton not only to H~2~O, but also to other bases present in the solution.