IUPAC-NIST Solubilities Database

IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Solubility System: Calcium formate with Copper(II) formate and Water

Components:
   (1) Calcium formate; Ca(CHO2)2; [544-17-2]  NIST Chemistry WebBook for detail
   (2) Copper(II) formate; Cu(CHO2)2; [544-19-4]  NIST Chemistry WebBook for detail
   (3) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Portnova, S.M.; Palitskaya, T.A., Zh. Neorg. Khim. 37, 2126-31 (1992).

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 Ca(CHO₂)₂-Cu(CHO₂)₂-H₂O system at 25 °C.
Chemical₁	Phase	Mass Fraction w₁	m₁ [mol kg-1]^a	Chemical₂	Mass Fraction w₂	m₂ [mol kg-1]^a	Solid Phase(s)^b
Cu(CHO2)2	Liquid	---	---	Ca(CHO2)2	14.43	1.296	A
Cu(CHO2)2	Liquid	0.69	0.052	Ca(CHO2)2	13.69	1.229	A
Cu(CHO2)2	Liquid	2.31	0.180	Ca(CHO2)2	14.09	1.295	A
Cu(CHO2)2	Liquid	4.62	0.371	Ca(CHO2)2	14.20	1.344	A
Cu(CHO2)2	Liquid	4.97	0.402	Ca(CHO2)2	14.48	1.382	A
Cu(CHO2)2	Liquid	5.08	0.411	Ca(CHO2)2	14.40	1.374	A
Cu(CHO2)2	Liquid	5.18	0.420	Ca(CHO2)2	14.56	1.394	A+B
Cu(CHO2)2	Liquid	5.62	0.457	Ca(CHO2)2	14.25	1.367	B
Cu(CHO2)2	Liquid	6.11	0.496	Ca(CHO2)2	13.72	1.315	B
Cu(CHO2)2	Liquid	9.47	0.791	Ca(CHO2)2	12.53	1.235	B
Cu(CHO2)2	Liquid	10.45	0.881	Ca(CHO2)2	12.30	1.224	B
Cu(CHO2)2	Liquid	10.93	0.925	Ca(CHO2)2	12.12	1.210	B
Cu(CHO2)2	Liquid	10.96	0.928	Ca(CHO2)2	12.14	1.213	B+C
Cu(CHO2)2	Liquid	10.91	0.922	Ca(CHO2)2	12.03	1.200	C
Cu(CHO2)2	Liquid	10.80	0.907	Ca(CHO2)2	11.64	1.153	C
Cu(CHO2)2	Liquid	10.38	0.850	Ca(CHO2)2	10.15	0.982	C
Cu(CHO2)2	Liquid	9.96	0.805	Ca(CHO2)2	9.51	0.908	C
Cu(CHO2)2	Liquid	9.25	0.737	Ca(CHO2)2	9.01	0.847	C
Cu(CHO2)2	Liquid	9.47	0.742	Ca(CHO2)2	7.43	0.687	C+D
Cu(CHO2)2	Liquid	8.64	0.657	Ca(CHO2)2	5.79	0.520	D
Cu(CHO2)2	Liquid	8.56	0.647	Ca(CHO2)2	5.34	0.477	D
Cu(CHO2)2	Liquid	8.46	0.629	Ca(CHO2)2	4.00	0.351	D
Cu(CHO2)2	Liquid	8.34	0.615	Ca(CHO2)2	3.34	0.291	D
Cu(CHO2)2	Liquid	8.28	0.608	Ca(CHO2)2	3.02	0.262	D
Cu(CHO2)2	Liquid	8.24	0.599	Ca(CHO2)2	2.24	0.192	D
Cu(CHO2)2	Liquid	8.82	0.636	Ca(CHO2)2	0.95	0.081	D
Cu(CHO2)2	Liquid	9.05	0.654	Ca(CHO2)2	0.83	0.071	D
Cu(CHO2)2	Liquid	9.46	0.680	Ca(CHO2)2	---	---	D

Notes:
   ^a  The molality values were calculated by the compilers.
   ^b  The solid phases are: A = Ca(CHO₂)₂; B = Ca₂Cu(CHO₂)₆; C = Cu(CHO₂)₂•2H₂O; D = Cu(CHO₂)₂•4H₂O.

Method/Apparatus/Procedure:
   The isothermal solubility method was used. Four weeks were allowed for equilibration. The copper content was determined iodometrically. The calcium ion content was determined complexometrically¹ using diethyldithiocarbamate. The composition of the solid phase was determined by the Schreinemakers' method. X-ray diffraction, DT and TG, DTG, T analysis were also used.

Source and Purity of Materials:
   The copper formate was prepared by the reaction of p.a. grade. CuCO₃ with p.a. grade formic acid. The calcium formate was prepared by the reaction of pure Ca(OH) ₂ with p.a. grade formic acid.

Estimated Errors:
   Solubility: No information is given.
   Temperature: No information is given.

References:
   ¹S. M. Portnova, I. V. Balakaeva, and Yu. I. Krassilov, Zh. Neorg. Khim. 35, 230 (1990).