IUPAC-NIST Solubilities Database

IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Solubility System: Lanthanum formate with Urea and Water

Components:
   (1) Lanthanum formate; La(CHO2)3; [2081-11-0]  NIST Chemistry WebBook for detail
   (2) Urea; CH4N2O; [57-13-6]  NIST Chemistry WebBook for detail
   (3) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Portnova, S.M.; Lyashchenko, A.K., Zh. Neorg. Khim. 27, 2953-8 (1982).

Variables:

   Concentration = Composition at 50 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 La(CHO₂)₃-CH₄N₂O-H₂O system at 50 °C.
Chemical₁	Phase	Mass Fraction w₁	m₁ [mol kg-1]^a	Chemical₂	Mass Fraction w₂	m₂ [mol kg-1]^a	Solid Phase(s)^b
La(CHO2)3	Liquid	0.30	0.011	CH4N2O	---	---	A
La(CHO2)3	Liquid	0.02	0.0008	CH4N2O	9.89	1.83	A
La(CHO2)3	Liquid	0.01	0.0005	CH4N2O	31.09	7.513	A
La(CHO2)3	Liquid	0.01	0.0008	CH4N2O	53.71	19.32	A
La(CHO2)3	Liquid	0.05	0.004	CH4N2O	55.18	20.52	A

Notes:
   ^a  The molality values were calculated by the compilers and the editor.
   ^b  The solid phase is: A = La(CHO₂)₃.

Method/Apparatus/Procedure:
   The isothermal method was used. The lanthanum content of the solid and liquid phases was determined complexometrically using Complexon III and Methylthymol Blue as indicator. The nitrogen content of the liquid phase was determined iodometrically. The nitrogen content of the solid phases was determined by the Dumas method.

Source and Purity of Materials:
   Lanthanum formate was obtained by reaction of lanthanum oxide with formic acid.

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