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Title: Thermodynamics of the complexes of aqueous iron(III), aluminum, and several divalent cations with EDTA: heat capacities, volumes, and variations in stability in temperature

Abstract

Apparent molar heat capacities and volumes at 25 /sup 0/C have been determined for aqueous H/sub 2/EDTA/sup 2 -/ and for the complexes of aqueous EDTA/sup 4 -/ with Ca/sup 2 +/, Mg/sup 2 +/, Al/sup 3 +/, Fe/sup 3 +/, Mn/sup 2 +/, Co/sup 2 +/, Ni/sup 2 +/, Cu/sup 2 +/, and Zn/sup 2 +/, all as the sodium salts. The standard-state partial molar heat capacities, anti C/sub p//sup 0/, and volumes, anti V/sup 0/, derived from these measurements were treated by using the simple Born model to calculate the coulombic effects on the surrounding water. The non-Coulombic contributions to anti C/sub p//sup 0/ and anti V/sup 0/ are very similar for all the complexes, and small systematic variations are consistent with known structures of the aqueous complexes. Values for the partial molar properties anti C/sub p/ and anti V were combined with critically evaluated literature data to calculate the temperature dependence of the stability constants at 0.1 m ionic strength. The relative stability of the complex ions MgEDTA/sup 2 -/(aq), FeEDTA/sup -/(aq), and AlEDTA/sup -/(aq) increase sharply relative to CaEDTA/sup 2 -/(aq) and the complexes with other M/sup 2 +/ ions. 58 references, 6 figures, 7 tables.

Authors:
;
Publication Date:
Research Org.:
Alberta Research Council, Edmonton
OSTI Identifier:
5896295
Resource Type:
Journal Article
Journal Name:
J. Phys. Chem.; (United States)
Additional Journal Information:
Journal Volume: 89:25
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 04 OIL SHALES AND TAR SANDS; ALUMINIUM COMPLEXES; SPECIFIC HEAT; VOLUME; CALCIUM COMPLEXES; COBALT COMPLEXES; COPPER COMPLEXES; EDTA; IRON COMPLEXES; MAGNESIUM COMPLEXES; MANGANESE COMPLEXES; NICKEL COMPLEXES; ZINC COMPLEXES; EXPERIMENTAL DATA; STRUCTURAL CHEMICAL ANALYSIS; TEMPERATURE DEPENDENCE; ALKALINE EARTH METAL COMPLEXES; AMINO ACIDS; CARBOXYLIC ACIDS; CHELATING AGENTS; COMPLEXES; DATA; INFORMATION; NUMERICAL DATA; ORGANIC ACIDS; ORGANIC COMPOUNDS; PHYSICAL PROPERTIES; THERMODYNAMIC PROPERTIES; TRANSITION ELEMENT COMPLEXES; 400301* - Organic Chemistry- Chemical & Physicochemical Properties- (-1987); 040500 - Oil Shales & Tar Sands- Properties & Composition

Citation Formats

Hovey, J K, and Tremaine, P R. Thermodynamics of the complexes of aqueous iron(III), aluminum, and several divalent cations with EDTA: heat capacities, volumes, and variations in stability in temperature. United States: N. p., 1985. Web. doi:10.1021/j100271a047.
Hovey, J K, & Tremaine, P R. Thermodynamics of the complexes of aqueous iron(III), aluminum, and several divalent cations with EDTA: heat capacities, volumes, and variations in stability in temperature. United States. https://doi.org/10.1021/j100271a047
Hovey, J K, and Tremaine, P R. Thu . "Thermodynamics of the complexes of aqueous iron(III), aluminum, and several divalent cations with EDTA: heat capacities, volumes, and variations in stability in temperature". United States. https://doi.org/10.1021/j100271a047.
@article{osti_5896295,
title = {Thermodynamics of the complexes of aqueous iron(III), aluminum, and several divalent cations with EDTA: heat capacities, volumes, and variations in stability in temperature},
author = {Hovey, J K and Tremaine, P R},
abstractNote = {Apparent molar heat capacities and volumes at 25 /sup 0/C have been determined for aqueous H/sub 2/EDTA/sup 2 -/ and for the complexes of aqueous EDTA/sup 4 -/ with Ca/sup 2 +/, Mg/sup 2 +/, Al/sup 3 +/, Fe/sup 3 +/, Mn/sup 2 +/, Co/sup 2 +/, Ni/sup 2 +/, Cu/sup 2 +/, and Zn/sup 2 +/, all as the sodium salts. The standard-state partial molar heat capacities, anti C/sub p//sup 0/, and volumes, anti V/sup 0/, derived from these measurements were treated by using the simple Born model to calculate the coulombic effects on the surrounding water. The non-Coulombic contributions to anti C/sub p//sup 0/ and anti V/sup 0/ are very similar for all the complexes, and small systematic variations are consistent with known structures of the aqueous complexes. Values for the partial molar properties anti C/sub p/ and anti V were combined with critically evaluated literature data to calculate the temperature dependence of the stability constants at 0.1 m ionic strength. The relative stability of the complex ions MgEDTA/sup 2 -/(aq), FeEDTA/sup -/(aq), and AlEDTA/sup -/(aq) increase sharply relative to CaEDTA/sup 2 -/(aq) and the complexes with other M/sup 2 +/ ions. 58 references, 6 figures, 7 tables.},
doi = {10.1021/j100271a047},
url = {https://www.osti.gov/biblio/5896295}, journal = {J. Phys. Chem.; (United States)},
number = ,
volume = 89:25,
place = {United States},
year = {1985},
month = {12}
}