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Indian Journal of Chemistry -Section A (IJC-A) >
IJC-A Vol.51A [2012] >
IJC-A Vol.51A(03) [March 2012] >
| Title: | Synergetic influence of mercaptoacetic acid on the reaction of thiourea with methylene blue in acidic medium |
| Authors: | Mishra, K K
Dwivedi, Upasana |
| Keywords: | Kinetics
Reaction Mechanism
Synergetic Effect
Mercaptoacetic Acid
Thiourea-Methylene Blue Reaction |
| Issue Date: | 2-Mar-2012 |
| Abstract: | Thiourea and
methylene blue interact in a mole ratio of 2:1 in the presence of HCl forming
the corresponding disulphide and leucomethylene blue. The order in thiourea is
unity while that in methylene blue is zero at higher concentrations (ca.>2.5×10-5 M). At lower concentrations, the order
in methylene blue is -1/2; this kinetic deviation depends on the nature of the
thiol acid exhibiting synergetic effect. Mercaptoacetic acid does not react
with methylene blue under the prevailing conditions; however it exerts a
synergetic effect on the reaction. The rate increases linearly on increasing [H+]
with the reaction having a large negative entropy of activation. Electrospray
induced mass spectrometry, 1H NMR and FTIR data indicate the
participation of a persulphide-like species formed due to
thiourea–mercaptoacetic acid interaction, which is perhaps responsible for the
synergetic effect of mercaptoacetic acid. |
| Page(s): | 458-463 |
| CC License: |  CC Attribution-Noncommercial-No Derivative Works 2.5 India |
| Source: | IJC-A Vol.51A(03) [March 2012]
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