IUPAC-NIST Solubility Database
NIST Standard Reference Database 106


Glass Ball as Bullet Solubility System: Manganese formate with Water

Components:
   (1) Manganese formate; Mn(CHO2)2; [3251-96-5]  NIST Chemistry WebBook for detail
   (2) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Balarew, C.; Stoilova, D.G.; Vassileva, V.Z., Dokl. Bolg. Acad. Nauk 35, 933 (1982).

Variables:
   Temperature = 10 ºC to 80 ºC

Prepared By:
   Chr. Balarew and St. Trendafilova

Experimental Data:   (Notes on the Nomenclature)
(Please see footnotes following the table(s).)
  
Solubility polytherm of the Mn(CHO2)2-H2O system.
t/°CPhaseMass Fraction w1m1 [mol kg-1]aSolid Phase(s)b
10Liquid phase Mn(CHO2)25.330.388A
15Liquid phase Mn(CHO2)25.960.437A
20Liquid phase Mn(CHO2)26.150.452A
25Liquid phase Mn(CHO2)26.280.462A
30Liquid phase Mn(CHO2)26.690.495A
35Liquid phase Mn(CHO2)26.970.517A
40Liquid phase Mn(CHO2)27.470.557A
45Liquid phase Mn(CHO2)27.830.586A
50Liquid phase Mn(CHO2)28.080.606A
55Liquid phase Mn(CHO2)29.090.690A
60Liquid phase Mn(CHO2)29.680.739A
65Liquid phase Mn(CHO2)29.800.749A
70Liquid phase Mn(CHO2)211.540.900A
75Liquid phase Mn(CHO2)211.750.918A
80Liquid phase Mn(CHO2)212.440.980A
Notes:
   a  These values were calculated by the compilers.
   b  The solid phase is: A = Mn(CHO2)2•2H2O.

Method/Apparatus/Procedure:
   Equilibrium was reached after about 2 days of stirring using the isothermal decrease of supersaturation method. The manganese content of the solid and liquid phases was determined complexometrically with Complexon III at pH 9.5-10, using Eriochrome Black T as indicator after adding hydroxylamine. The solid phases were studied microscopically and by the use of differential thermal analysis.

Source and Purity of Materials:
   Manganese formate was prepared by the reaction of dilute formic acid with manganese carbonate. All reagents were p.a. grade.

Estimated Errors:
   Solubility: The solubility of the salt was determined in a slight excess of formic acid (about 2%) in order to inhibit hydrolysis.