IUPAC-NIST Solubility Database
NIST Standard Reference Database 106


Glass Ball as Bullet Solubility System: Potassium formate with Cadmium formate and Water

Components:
   (1) Potassium formate; KCHO2; [590-29-4]  NIST Chemistry WebBook for detail
   (2) Cadmium formate; Cd(CHO2)2; [4464-23-7]  NIST Chemistry WebBook for detail
   (3) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Nadzharyan, K.A.; Itkina, L.S.; Lepeshkov, I.N., Zh. Neorg. Khim. 26, 519 (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 KCHO2-Cd(CHO2)2-H2O system at 25 °C.
Chemical1PhaseMass Fraction w1m1 [mol kg-1]Chemical2Mass Fraction w2m2 [mol kg-1]Solid Phase(s)a
KCHO2Liquid81.8253.51Cd(CHO2)2------A
KCHO2Liquid79.1647.42Cd(CHO2)20.990.246A+B
KCHO2Liquid76.0939.63Cd(CHO2)21.080.234B
KCHO2Liquid70.0629.14Cd(CHO2)21.350.233B
KCHO2Liquid62.1921.07Cd(CHO2)22.710.381B
KCHO2Liquid60.5519.91Cd(CHO2)23.280.448B
KCHO2Liquid58.6718.94Cd(CHO2)24.500.604B
KCHO2Liquid57.3818.42Cd(CHO2)25.570.743B
KCHO2Liquid56.1517.68Cd(CHO2)26.090.797B
KCHO2Liquid51.4916.13Cd(CHO2)210.531.373B+C
KCHO2Liquid49.5914.62Cd(CHO2)210.071.233C
KCHO2Liquid41.8610.37Cd(CHO2)210.141.043C
KCHO2Liquid35.548.054Cd(CHO2)211.991.129C
KCHO2Liquid29.886.540Cd(CHO2)214.791.136C
KCHO2Liquid25.245.503Cd(CHO2)220.221.831C
KCHO2Liquid22.144.923Cd(CHO2)224.392.253C+D
KCHO2Liquid20.774.241Cd(CHO2)221.001.781D
KCHO2Liquid18.413.520Cd(CHO2)219.401.541D
KCHO2Liquid12.732.127Cd(CHO2)216.091.117D
KCHO2Liquid--Cd(CHO2)214.100.811D
Notes:
   a  The solid phases are: A = KCHO2; B = K3Cd(CHO2)5; C = KCd(CHO2)3; D = Cd(CHO2)2•2H2O.

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 3 weeks. The potassium content of both phases was determined by the tetraphenylborate method. The cadmium content was determined complexometrically. The composition of the solid phases was determined by Schreinemakers' method.

Source and Purity of Materials:
   KCHO2 was prepared by neutralizing 85% formic acid with p.a. grade KOH. Cadmium formate was obtained from p.a. grade cadmium carbonate.

Estimated Errors:

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