IUPAC-NIST Solubilities Database

IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Solubility System: Calcium formate with Boric acid and Water

Components:
   (1) Boric acid; H3BO3; [10043-35-3]  NIST Chemistry WebBook for detail
   (2) Calcium formate; Ca(CHO2)2; [544-17-2]  NIST Chemistry WebBook for detail
   (3) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Eremeeva, I.L.; Kalacheva, V.G.; Schwartz, E. M., Zh. Neorg. Khim. 22, 861-2 (1977).

Variables:

   Concentration = Composition at 25 ºC

Prepared By:
   St. Tepavicharova and St. Trendafilova

Experimental Data:   (Notes on the Nomenclature)
(Please see footnotes following the table(s).)

Solubility values in the Ca(CHO₂)₂-H₃BO₃-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
Ca(CHO2)2	Liquid	14.43	1.30	H3BO3	0.0	0.0	A
Ca(CHO2)2	Liquid	14.30	1.30	H3BO3	1.46	0.28	A
Ca(CHO2)2	Liquid	13.98	1.29	H3BO3	2.60	0.50	A
Ca(CHO2)2	Liquid	13.80	1.28	H3BO3	3.09	0.60	A
Ca(CHO2)2	Liquid	13.70	1.29	H3BO3	4.46	0.88	A
Ca(CHO2)2	Liquid	13.90	1.31	H3BO3	4.40	0.87	A
Ca(CHO2)2	Liquid	13.94	1.32	H3BO3	4.61	0.92	A
Ca(CHO2)2	Liquid	13.80	1.31	H3BO3	5.25	1.05	“
Ca(CHO2)2	Liquid	13.5	1.28	H3BO3	5.75	1.15	A+B
Ca(CHO2)2	Liquid	12.80	1.21	H3BO3	5.65	1.12	B
Ca(CHO2)2	Liquid	11.0	1.01	H3BO3	5.64	1.00	B
Ca(CHO2)2	Liquid	10.0	0.91	H3BO3	5.59	1.07	B
Ca(CHO2)2	Liquid	7.22	0.64	H3BO3	5.58	1.03	B
Ca(CHO2)2	Liquid	6.40	0.56	H3BO3	5.53	1.02	B
Ca(CHO2)2	Liquid	3.70	0.31	H3BO3	5.48	0.98	B
Ca(CHO2)2	Liquid	1.60	0.13	H3BO3	5.52	0.96	B
Ca(CHO2)2	Liquid	0.0	0.0	H3BO3	5.51	0.94	B

Notes:
   ^a  The molality values were calculated by the compilers.
   ^b  The solid phases are: A = Ca(CHO₂)₂; B = H₃BO₃.

Method/Apparatus/Procedure:
   The isothermal method was used. Equilibrium was established when a constant pH, diffraction coefficient and concentration of H₃BO₃ were reached. The Ca²⁺ and B³⁺ contents were determined as CaO and B₂O₃. The composition of the solid phases was determined by the Schreinemakers method.

Source and Purity of Materials:
   Ca(CHO₂)₂ was prepared by reaction of CaCO₃ with CH₂O₂. The product was recrystallized twice. Suprapure grade boric acid was used.

Estimated Errors:

   Temperature: ± 0.02 °C.