INFLUENCE OF TEMPERATURE ON THE STABILITY OF 2-ETHYLIMIDAZOLE AU (III) COMPLEXES
Rubrics: SCIENTIFIC ARTICLES
Authors:
1.
Tajik National University
(Professor)
Dushanbe, Tajikistan
Dushanbe, Tajikistan
2.
Tajik National University
Dushanbe, Tajikistan
Dushanbe, Tajikistan
3.
Tajik National University
(Assistant)
Dushanbe, Tajikistan
Dushanbe, Tajikistan
Type:
Article
Pages:
from 58
to 64
Status:
Published
Received:
02.09.2022
Accepted:
19.09.2022
Published:
23.09.2022
Language:
Russian
Keywords:
potentiometry, step complexation, gold (III), 2-ethylimidazole, stability constant, temperature factor
Abstract (English):
This article deals with the complexation of gold (III) with 2-ethylimidazole at a temperature range of 278-328 K by potentiometric titration. The reduction of the Au/[AuCl4]- system potential during the titration process at all temperatures under study indicates a reduction of the equilibrium concentration of [AuCl4]- and their coupling into complexes. The non-linearity of the dependence of E on lgCL is characteristic for the systems in which stepwise complexation occurs. We calculated the common stability constants of the complexes [Au(2-EI)Cl3] and [Au(2-EI)2Cl2]Cl (at 298 K lgβ1 = 6.14±0.06; lgβ2 = 13.18±0.08). The stability of the complexes grows with increasing of temperature. The temperature factor affects the stability of the bisubstituted complex to a greater extent (at a rise in temperature by 50 °C the stability of the bisubstituted complex increases by 2.69 log units, at the same temperature interval the stability of the monosubstituted complex increases by 1.32 log units).
This article deals with the complexation of gold (III) with 2-ethylimidazole at a temperature range of 278-328 K by potentiometric titration. The reduction of the Au/[AuCl4]- system potential during the titration process at all temperatures under study indicates a reduction of the equilibrium concentration of [AuCl4]- and their coupling into complexes. The non-linearity of the dependence of E on lgCL is characteristic for the systems in which stepwise complexation occurs. We calculated the common stability constants of the complexes [Au(2-EI)Cl3] and [Au(2-EI)2Cl2]Cl (at 298 K lgβ1 = 6.14±0.06; lgβ2 = 13.18±0.08). The stability of the complexes grows with increasing of temperature. The temperature factor affects the stability of the bisubstituted complex to a greater extent (at a rise in temperature by 50 °C the stability of the bisubstituted complex increases by 2.69 log units, at the same temperature interval the stability of the monosubstituted complex increases by 1.32 log units).
Keywords:
potentiometry, step complexation, gold (III), 2-ethylimidazole, stability constant, temperature factor
potentiometry, step complexation, gold (III), 2-ethylimidazole, stability constant, temperature factor
