conductometric studies of the thermodynamics of complexation of zn2+, ni2+, co2+, pb2+, mn2+, cu2+ ions with 1,13-bis(8-quinolyl)-1,4,7,10,13-pentaoxatridecane in binary solvent mixtures
نویسندگان
چکیده
the complexation reaction between 1,13-bis(8-quinolyl)-1,4,7,10,13-pentaoxatridecane (kryptofix5) ligand with zn2+, ni2+, co2+, pb2+, mn2+ and cu2+ ions were studied conductometrically in different acetonitrile-nitromethane (an-nm) and acetonitrile-methanol (an-meoh) mixtures. the formation constants of the resulting 1:1 complexes were calculated from the computer fitting of the molar conductance in various mole ratios. the enthalpy and entropy changes of the complexation reactions were derived from conductometric titrations in different an-nm mixtures at various temperatures. the results revealed that kryptofix5 forms very stable 1:1 complexes with mentioned cations in all an-nm and an-meoh mixtures. it was found that the stability of the resulting complexes decreased with increasing nitromethane or methanol in the solvent mixture. the tδs° vs. δh° plot of all thermodynamic data obtained shows a fairly good linear correlation indicating the existence of enthalpy-entropy compensation in the complexation reactions.
منابع مشابه
Conductometric Studies of the Thermodynamics of Complexation of Zn2+, Ni2+, Co2+, Pb2+, Mn2+, Cu2+ Ions with 1,13-Bis(8-Quinolyl)-1,4,7,10,13-Pentaoxatridecane in Binary Solvent Mixtures
The complexation reaction between 1,13-bis(8-quinolyl)-1,4,7,10,13-pentaoxatridecane (Kryptofix5) ligand with Zn2+, Ni2+, Co2+, Pb2+, Mn2+ and Cu2+ ions were studied conductometrically in different AcetoNitrile-NitroMethane (AN-NM) and AcetoNitrile-Methanol (AN-MeOH) mixtures. The formation constants of the resulting...
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عنوان ژورنال:
iranian journal of chemistry and chemical engineering (ijcce)ناشر: iranian institute of research and development in chemical industries (irdci)-acecr
ISSN 1021-9986
دوره 31
شماره 3 2012
میزبانی شده توسط پلتفرم ابری doprax.com
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