IUPAC-NIST Solubilities Database

IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Solubility System: Sodium formate with Formic Acid and Water

Components:
   (1) Formic acid; CH2O2; [64-18-6]  NIST Chemistry WebBook for detail
   (2) Sodium formate; NaCHO2; [141-53-7]  NIST Chemistry WebBook for detail
   (3) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Tatsievskaya, G.I.; Konovalova, N.N.; Kushner, T.M.; Serafimov, L.A., Tr. Mosk. Inst. Tonkol Khim. Tekhnol. 3, 109 (1973).

Variables:

   Concentration = Composition at boiling temperatures (374.6 K to 421.6 K)

Prepared By:
   T. A. Ageyeva

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

Solubility values in the NaCHO₂-CH₂O₂-H₂O system at boiling temperatures.
Chemical₁	Mass Fraction w₁	10⁰ * Mole Fraction₁^a	Chemical₂	Mass Fraction w₂	Mole Fraction₂^a	Chemical₃	Mass Fraction w₃	Mole Fraction₃^a
NaCHO2	59.6	50.0	CH2O2	40.4	50.0	H2O	0.0	0.0
NaCHO2	59.4	44.4	CH2O2	34.3	37.9	H2O	6.3	18
NaCHO2	61.1	41.4	CH2O2	26.3	26.3	H2O	12.6	32.2
NaCHO2	61.4	37.4	CH2O2	18.6	16.7	H2O	20.0	45.9
NaCHO2	62.9	36.2	CH2O2	12.6	10.7	H2O	24.5	53.2
NaCHO2	65.4	35.4	CH2O2	4.8	3.8	H2O	29.8	60.8
NaCHO2	65.5	35.3	CH2O2	4.5	3.6	H2O	30.0	61.1
NaCHO2	66.7	34.7	CH2O2	0.0	0.0	H2O	33.3	65.3

Notes:
   ^a  These values were calculated by the compiler.

Method/Apparatus/Procedure:
   The polythermal titration method was used. The transition from a homogeneous state to a saturated solution was determined by the appearance of a suspension which disappeared after boiling for 6 h. The concentration titration step was about 0.3 mass %. Boiling points were determined ebulliometrically at 101.325 kPa. The NaCHO₂ and CH₂O₂ contents were determined by titration with a 0.4 N HCl solution in methanol using Eriochrome Black T as the indicator. The water content was determined by the Fisher titration method.

Source and Purity of Materials:
   The NaCHO₂ was recrystallized followed by drying. Purity was not specified. CH₂O₂ was purified by a method described elsewhere,¹ b.p. 373.9 K at 101325 kPa; n = 1.3714. The water was distilled.

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

References:
   ¹ T. M. Kushner, G. I. Tatsievskaya, and L. A. Serafimov, Zh. Fiz. Khim. 41, 237 (1967).