Home
Introduction
Search Menu
IUPAC Series (PDF)
Reference
Version History
About the Project
Disclaimer
Contact Us
Acknowledgements
IUPAC-NIST Solubility Database
NIST Standard Reference Database 106
Solubility System:
Iron formate with Cadmium formate and Water
Components:
(1) Cadmium formate; Cd(CHO2)2; [4464-23-7]
NIST Chemistry WebBook
for detail
(2) Iron formate; Fe(CHO2)2; [3047-59-4]
NIST Chemistry WebBook
for detail
(3) Water; H2O; [7732-18-5]
NIST Chemistry WebBook
for detail
Original Measurements:
Vasileva, V., Cryst. Res.Technol. 31, 993-1000 (1996).
Variables:
Concentration = Composition at 25 ºC
Prepared By:
Chr. Balarew and St. Trendafilova
Experimental Data:
(Notes on the Nomenclature)
(Please see footnotes following the table(s).)
Solubility values in the Fe(CHO
2
)
2
-Cd(CHO
2
)
2
-H
2
O system at 25 °C.
Chemical
1
Phase
Mass Fraction w
1
m
1
[mol kg-1]
a
Chemical
2
Mass Fraction w
2
m
2
[mol kg-1]
a
Solid Phase(s)
b
Distribution Coefficient
Cd2+/Fe2+
Distribution Coefficient
Fe2+/Cd2+
Fe(CHO2)2
Liquid
4.20
0.300
Cd(CHO2)2
0.00
0.000
A
0.00
0.00
Fe(CHO2)2
Liquid
3.54
0.256
Cd(CHO2)2
1.72
0.089
B
0.43
2.33
Fe(CHO2)2
Liquid
3.25
0.236
Cd(CHO2)2
2.48
0.129
B
0.46
2.17
Fe(CHO2)2
Liquid
2.89
0.211
Cd(CHO2)2
3.42
0.180
B
0.44
2.27
Fe(CHO2)2
Liquid
2.36
0.173
Cd(CHO2)2
4.39
0.232
B
0.46
2.17
Fe(CHO2)2
Liquid
2.17
0.161
Cd(CHO2)2
5.85
0.314
B
0.43
2.33
Fe(CHO2)2
Liquid
1.89
0.142
Cd(CHO2)2
7.03
0.381
B
0.47
2.13
Fe(CHO2)2
Liquid
1.40
0.106
Cd(CHO2)2
8.33
0.455
B
0.46
2.17
Fe(CHO2)2
Liquid
1.06
0.081
Cd(CHO2)2
9.49
0.521
B
0.47
2.13
Fe(CHO2)2
Liquid
0.00
0.000
Cd(CHO2)2
12.45
0.702
C
Notes:
a
The molality values were calculated by the compilers.
b
The solid phases are: A = Fe(CHO
2
)
2
•2H
2
O; B = (Fe,Cd)(CHO
2
)
2
•2H
2
O; C = Cd(CHO
2
)
2
•2H
2
O.
Method/Apparatus/Procedure:
The solubility was studied by the KHLOPIN method for isothermal decrease of supersaturation. Equilibrium was reached in about 15-20 h. The concentration of Fe
2+
, Cd
2+
was determined by an atomic absorption method. The solid phase composition was calculated by the variant of Schreinemakers method for algebraic indirect identification of the solid-phase composition.
1
X-ray powder diffraction analysis was also used.
Source and Purity of Materials:
The formates of iron(II) and cadmium were prepared by dissolving iron powder and cadmium carbonate, respectively, in diluted(1:1) formic acid at 70-80 °C. The reagents used were p.a. grade.
Estimated Errors:
Solubility: The solubility was determined in a slight excess of formic acid (2 mass %), to suppress salt hydrolysis and to prevent Fe
2+
oxidation.
Temperature: Not given.
References:
1
D. Trendafelov and Chr. Balarew, Comm. Dept. Chem. Bulg. Acad. Sci.
1
, 73 (1968).