IUPAC-NIST Solubilities Database

IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Solubility System: Strontium formate with Copper formate and Water

Components:
   (1) Copper formate; Cu(CHO2)2; [544-19-4]  NIST Chemistry WebBook for detail
   (2) Strontium formate; Sr(CHO2)2; [592-89-2]  NIST Chemistry WebBook for detail
   (3) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Portnova, S.M.; Krassilov, Yu. I.; Kuznetzov, N.T.; Balakaeva, I.V., Zh. Neorg. Khim. 35, 237-41 (1990).

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 Ba(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
Ba(CHO2)2	Liquid	---	---	Cu(CHO2)2	9.46	0.680	A
Ba(CHO2)2	Liquid	5.79	0.299	Cu(CHO2)2	8.94	0.683	A
Ba(CHO2)2	Liquid	10.78	0.598	Cu(CHO2)2	9.96	0.818	A
Ba(CHO2)2	Liquid	13.26	0.773	Cu(CHO2)2	11.30	0.975	A
Ba(CHO2)2	Liquid	13.44	0.780	Cu(CHO2)2	10.81	0.929	A+B
Ba(CHO2)2	Liquid	13.28	0.769	Cu(CHO2)2	10.76	0.922	B
Ba(CHO2)2	Liquid	12.99	0.742	Cu(CHO2)2	10.05	0.850	B
Ba(CHO2)2	Liquid	15.05	0.865	Cu(CHO2)2	8.46	0.720	B
Ba(CHO2)2	Liquid	14.68	0.798	Cu(CHO2)2	4.39	0.353	B
Ba(CHO2)2	Liquid	15.36	0.829	Cu(CHO2)2	3.14	0.251	B
Ba(CHO2)2	Liquid	19.43	1.074	Cu(CHO2)2	1.05	0.086	B
Ba(CHO2)2	Liquid	24.22	1.415	Cu(CHO2)2	0.52	0.045	B+C
Ba(CHO2)2	Liquid	24.20	1.410	Cu(CHO2)2	0.31	0.027	C
Ba(CHO2)2	Liquid	26.83	1.612	Cu(CHO2)2	---	---	C

Notes:
   ^a  The molality values were calculated by the compilers.
   ^b  The solid phases are: A = Cu(CHO₂)₂•4H₂O; B = Ba₂Cu(CHO₂)₆•4H₂O; C = Ba(CHO₂)₂.

Method/Apparatus/Procedure:
   The isothermal method was used. Four weeks were allowed for equilibration. The Cu²⁺ content was determined complexometrically. The Ba²⁺ content was determined gravimetrically as BaSO₄ after the Cu²⁺ was bound with Complexon III. The composition of the solid phases was determined by the Schreinemakers' method, by DT analysis and by x-ray fluorescence spectroscopy.

Source and Purity of Materials:
   The formates were obtained by neutralizing dilute formic acid with p.a. grade copper or barium oxides.

Estimated Errors:

   Temperature: Not given.