IUPAC-NIST Solubilities Database

IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Solubility System: Carbon dioxide with Potassium hydrogen oxalate and Water

Components:
   (1) Potassium hydrogen oxalate; C2HO4K; [127-95-7]  NIST Chemistry WebBook for detail
   (2) Carbon dioxide; CO2; [124-38-9]  NIST Chemistry WebBook for detail
   (3) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Van Slyke, D. D.; Sendroy, J., Jr.; Hastings, A. B.; Neill, J. M., J. Biol. Chem. 1928, 78, 765-99.

Variables:
   Temperature = 311.2 K
   Pressure = "atmospheric"
   Concentration = c₂/mol L^-1 = 0.300 and 0.600

Prepared By:
   Pirketta Scharlin

Experimental Data:   (Subscripts 1,2,3, ..., in column headings refer to components 1,2,3, ...)


t/°C	T/K	Temp Note	Pressure [mmHg]	Pressure Note	Concentration C₂ [mol/L]	Keunen coefficient, S	S Note	α	α Note
38.0	311.2	a	718.5	b	0.300	0.5328	d	0.5211	c
38.0	311.2	a	718.5	b	0.600	0.1340	d	0.4969	c

Notes:
   ^a  Calculated by the compiler.
   ^b  1 mmHg = 133.322 Pa = 1.33322 x 10^-3 bar
   ^c  α = Bunsen coefficient [cm³ (STP) cm^-3 atm^-1].
   ^d  S₁ = Kuenen coefficient [cm³ (STP) g^-1 atm^-1].

Method/Apparatus/Procedure:
   Solutions were saturated with CO₂ by a bubbling method:
Saturation by bubbling. The solution was placed in the saturating tube, the lower end of which was connected through a wash bottle with a Kipp CO₂ generator. The tube and the wash bottle were immersed in a constant temperature bath. CO₂ was bubbled through it rapidly for 30 minutes. The wash bottle was replaced by a mercury reservoir and the free gas was driven completely out of the saturating tube by admitting mercury underneath the solution. The CO₂ contents of the solutions were determined in the manometric gas apparatus (Refs 1 and 2).

Source and Purity of Materials:
   (1) From a Kipp CO₂ generator.
   (2) The KHC₂O₄ solutions were prepared from K₂C₂O₄ plus equimolar amounts of free oxalic acid crystals.
   (3) Distilled.

Estimated Errors:
   Solubility: δα/α = ± 0.005
   Temperature: δT/K = ± 0.1

References:
   1. Van Slyke, D. D.; Neill, J. M., J. Biol. Chem. 1924, 61, 523.
   2. Van Slyke, D.D.; Sendroy, J., Jr., J. Biol. Chem. 1927, 73, 127.