IUPAC-NIST Solubilities Database

IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Solubility System: Indole with Ethanol

Components:
   (1) 5-Methylindole; C9H9N; [614-96-0]  NIST Chemistry WebBook for detail
   (2) Indole; C8H7N; [120-72-9]  NIST Chemistry WebBook for detail

Original Measurements:
   Pucher, G.; Dehn, W.M., J. Am. Chem. Soc. 1921, 43, 1753-1758.

Variables:
   Temperature = Temperature

Prepared By:
   W.E. Acree, Jr.

Experimental Data:   (Notes on the Nomenclature)


T/K	Mole Fraction x₁	Mole Fraction x₂	Comment(s)
333.74	0.0000	1.0000	Solid Phase (2)
327.70	0.1051	0.8949	Solid Phase (2)
321.45	0.2006	0.7994	Solid Phase (2)
315.52	0.3021	0.6979	Solid Phase (2)
307.85	0.3998	0.6002	Solid Phase (2)
298.72	0.5007	0.4993	Solid Phase (2)
289.20	0.5990	0.4010	Solid Phase (1)
300.78	0.7006	0.2994	Solid Phase (1)
310.37	0.7999	0.2001	Solid Phase (1)
317.99	0.8996	0.1004	Solid Phase (1)
326.26	1.0000	0.0000	Solid Phase (1)

Notes:
     Authors report eutectic point occurs at x₁ = 0.5915 and T/K = 289.63.

Method/Apparatus/Procedure:
   Constant temperature bath and a precision thermometer.
Mixtures of known concentrations sealed in glass ampoules and placed in constant temperature to equilibrate. Samples were rotated while bath temperature slowly increased. Solubility determined by visual noting the same temperature at which the last trace of solid solute disappeared.

Source and Purity of Materials:
   (1) 99.9 %, Aldrich Chemical Company, Milwaukee, Wisconsin, USA, was used as received.
   (2) 99.0 %, Aldrich Chemical Company, was used as received from manufacturer.

Estimated Errors:

   Temperature: T/K: precision ± 0.02. x₁: ± 0.0001.