Table of Contents
ISRN Inorganic Chemistry
Volume 2013 (2013), Article ID 189394, 5 pages
Research Article

Complex Formation Equilibria between Ag(I) and Thioureas in Propan-2-ol

Department of Chemistry, University of Messina, Salita Sperone 31, Messina, Italy

Received 25 June 2013; Accepted 8 September 2013

Academic Editors: M. S. Masoud and J. Zhang

Copyright © 2013 Domenico De Marco. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The complex formation equilibria between Ag(I) and thiourea (Tu), N methyl-Thiourea (MeTu), N,N′-dimethyl-Thiourea (Me2Tu), N,N,N′,N′ Tetramethyl-Thiourea (Me4Tu), N-ethyl-Thiourea (EtTu), N,N′ diethyl-Thiourea (Et2Tu), and N,N′-Ethylen-Thiourea (EnTu) in propan-2-ol as solvent medium have been investigated by potentiometry within the temperature range 10°C–40°C and self-determined ionic medium by (AgNO3) concentration range m·dm−3 (no background electrolyte added). The experimental results can be interpreted with the stepwise formation of tris-coordinated complexes ( ; hereafter charge is omitted). The stability constants log and the standard thermodynamic changes in enthalpy ( ) and entropy ( ) for overall complex formation reactions ( ) have been evaluated. The reactions are exothermic in nature and entropy disfavored for all the investigated ligands. The standard enthalpy and entropy changes for the stepwise reactions have been evaluated by difference and . The stepwise enthalpy are mutually linearly related to the corresponding entropy changes with isoequilibrium temperatures , 305, and 363 K for , 2, or 3 respectively.