IUPAC-NIST Solubilities Database

IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Solubility System: Ammonium formate with Barium formate and Water

Components:
   (1) Ammonium formate; NH4CHO2; [540-69-2]  NIST Chemistry WebBook for detail
   (2) Barium formate; Ba(CHO2)2; [541-43-5]  NIST Chemistry WebBook for detail
   (3) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Itkina, L.S.; Nadzharyan, K.A.; Lepeshkov, I.N., Zh. Neorg. Khim. 26, 1086-91 (1981).

Variables:

   Concentration = Composition at 25 ºC.

Prepared By:
   Chr. Balarew and St. Trendafilova

Experimental Remarks:

   The molality values were calculated by the compilers.

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

Solubility values in the NH₄CHO₂-Ba(CHO₂)₂-H₂O system at 25 °C.
Chemical₁	Phase	Mass Fraction w₁	m₁ [mol kg-1]	Chemical₂	Mass Fraction w₂	m₂ [mol kg-1]	Solid Phase(s)^a
NH4CHO2	Liquid	60.53	24.32	Ba(CHO2)2	---	---	A
NH4CHO2	Liquid	59.08	23.81	Ba(CHO2)2	1.57	0.175	A+B
NH4CHO2	Liquid	58.41	23.19	Ba(CHO2)2	1.65	0.182	B
NH4CHO2	Liquid	56.54	21.46	Ba(CHO2)2	1.68	0.177	B
NH4CHO2	Liquid	51.23	17.23	Ba(CHO2)2	1.62	0.151	B
NH4CHO2	Liquid	39.60	10.69	Ba(CHO2)2	1.63	0.122	B
NH4CHO2	Liquid	38.50	10.29	Ba(CHO2)2	2.18	0.162	B
NH4CHO2	Liquid	36.72	9.537	Ba(CHO2)2	2.22	0.160	B
NH4CHO2	Liquid	24.78	5.457	Ba(CHO2)2	3.21	0.196	B
NH4CHO2	Liquid	11.57	2.333	Ba(CHO2)2	9.80	0.548	B
NH4CHO2	Liquid	---	---	Ba(CHO2)2	23.71	1.367	A

Notes:
   ^a  The solid phases are: A = NH₄CHO₂; B = Ba(CHO₂)₂.

Method/Apparatus/Procedure:
   The isothermal method was used. The mixtures were placed in glass vessels in a thermostat and stirred mechanically. Equilibrium was reached in 2 weeks. The ammonium content of both phases was determined by the tetraphenylborate method. The barium content was determined gravimetrically as BaSO₄. The composition of the solid phases was determined by Schreinemakers' method, by x-ray diffraction and by thermogravimetry.

Source and Purity of Materials:
   p.a. grade Ba(CHO₂)₂ was recrystallized twice from a 1% solution of formic acid. NH₄CHO₂ was prepared by passing ammonia into 90% formic acid. The crystals were washed with ethanol and vacuum dried over sulfuric acid.

Estimated Errors:

   Temperature: The temperature was kept constant to within ± 0.1°C.