IUPAC-NIST Solubilities Database

IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Solubility System: 2-Methylbutane with Water

Components:
   (1) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail
   (2) 2-Methylbutane; C5H12; [78-78-4]  NIST Chemistry WebBook for detail

Evaluator:
   G.T. Hefter, School of Mathematical and Physical Sciences, Murdoch University, Perth, W.A., Australia. July 1985.

Critical Evaluation:

   Quantitative solubility data for the 2-methylbutane (1) and water (2) system have been reported in the publications listed in Table 1.

The original data in all of these publications are compiled in the Data Sheets immediately following this Critical Evaluation.

In the Tables, which follow, solubility obtained by the Evaluator by graphical interpolation of original measurements in the Data Sheets are indicated by an asterisk (*). “Best” values have been obtained, where appropriate, by simple averaging. Uncertainty limits (σ_n) attached to these values do not have statistical significance and should be regarded only as a convenient representation of the spread of values rather than error limits.

For convenience, further discussion of this system will be divided into two parts.

1. THE SOLUBILITY OF 2 METHYLBUTANE (1) IN WATER (2)
The solubility data for 2-methylbutane in water are listed in Table 2 and are also plotted in Figure 1 . The data of Krzyzanowska and Szeliga (ref 7) have been excluded from this Evaluation as they do not appear to be independent of those reported by Price (ref 6).

At 298K, where comparison amongst independent values is possible, agreement is excellent. This gives added confidence to the values at other temperatures. A possible exception may be the value of Polak and Lu (ref 5) at 273 K which appears a little high (even though some increase in solubility of hydrocarbons in water is usually observed as the temperature approaches 273 K, e.g. the benzene-water system).

2. THE SOLUBILITY OF WATER (2) IN 2-METHYLBUTANE (1)

The solubility data for water in 2-methylbutane are listed in Table 3 and plotted in Figure 2 . In general the reported values are in reasonable agreement. The only exception appears to be the data of Pavlova et al. (ref 4) which are higher than other values. Although there are insufficient independent data to justify outright rejection of the values of Pavlova et al. at this stage, nevertheless, their data have not been used in determining “best” values (Table 3) and should be regarded with caution.

Experimental Data:   (Notes on the Nomenclature)

Table 1. Quantitative Solubility Studies of the 2- Methylbutane (1) - Water (2) System
Author	T/K	Reference	Solubility	Method
Black et al.	279-295	1	(2) in (1)	radiotracer
Englin et al.	273-293	2	(2) in (1)	analytical
McAuliffe	298	3	(1) in (2)	GLC
Pavlova et al.	293-333	4	mutual	GLC, Karl Fischer
Polak and Lu	273, 298	5	mutual	GLC, Karl Fischer
Price	298	6	(1) in (2)	GLC
Krzyzanowska and Szeliga	298	7	(1) in (2)	GLC

Table 2. Recommended (R) and Tentative Values of the Solubility of 2-Methylbutane (1) in Water (2)
T/K	Reference	Sol. Power	Solubility	Best Sol. Power	Best Solubility	Best Sol. Note	x₁ Power	x₁	x₁ Note
273	5	3	7.24 g(1)/100g sln	3	7.2 g(1)/100 g sln	a	5	1.8	a
293	4	3	4.69 g(1)/100g sln	3	4.7 g(1)/100g sln	-	5	1.2	-
298	3, 4, 5, 6	3	4.78, 4.86*, 4.96, 4.8 g(1)/100g sln	3	4.85 ± 0.07 (R) g(1)/100g sln	-	5	1.21 (R)	-
303	4	3	5.06* g(1)/100g sln	3	5.1 g(1)/100g sln	-	-	-
313	4	3	5.77 g(1)/100g sln	3	5.8 g(1)/100g sln	-	5	1.4	-
323	4	3	7.01 g(1)/100g sln	3	7.0 g(1)/100g sln	-	5	1.8	-
333	4	3	7.93 g(1)/100g sln	3	7.9 g(1)/100g sln	-	5	2.0	-

Table 3. Tentative Values of the Solubility of Water (2) in 2-Methylbutane (1)
T/K	Reference	Sol. Power	Solubility	Best Sol. Power	Best Solubility	Best Sol. Note	x₂ Power	x₂	x₂ Note
273	2, 5	3	3.2, 2.8 g(2)/100 g sln	3	3.0 ± 0.2 g(2)/100 g sln	a	4	1.2	a
278	1	3	4.3* g(2)/100 g sln	3	4.3 g(2)/100 g sln	a	4	1.7	a
283	1, 2	3	5.2*, 5.9 g(2)/100 g sln	3	5.5 ± 0.4 g(2)/100 g sln	a	4	2.2	a
288	1	3	6.5* g(2)/100 g sln	3	6.5 g(2)/100 g sln	a	4	2.6	a
293	1, 2, 4	3	9.2*, 11.2, 16.0 g(2)/100 g sln	3	10 ± 1 g(2)/100 g sln	a	4	4	a
298	4, 5	3	18*, 9.6 g(2)/100 g sln	3	10 g(2)/100 g sln	a	4	4	a
303	4	3	20* g(2)/100 g sln	-	-	-	-	-	-
313	4	3	25.7 g(2)/100 g sln	-	-	-	-	-	-
323	4	3	40* g(2)/100 g sln	-	-	-	-	-	-
333	4	3	58.5 g(2)/100 g sln	-	-	-	-	-	-

View Figure 1 for this Evaluation

View Figure 2 for this Evaluation

Notes:
Table 2^a  Value may be doubtful, see text.
Table 3^a  Data from ref 4 not included in calculation of "best" values, see text.

References: (Click a link to see its experimental data associated with the reference)

   1  Black, C.; Joris, G.G.; Taylor, H.S., J. Chem. Phys. 1948, 16, 537-43.
   2  Englin, B.A.; Plate, A.F.; Tugolukov, V.M. Pryanishnikova, M.A., Khim. Tekhnol. Topl. Masel 1965, 10, 42-6.
   3  McAuliffe, C., J. Phys. Chem. 1966, 70, 1267-75.
   4  Pavlova, S.P.; Pavlov, S.Yu.; Serafimov, L.A.; Kofman, L.S., Promyshlennost. Sinteticheskogo Kauchuka 1966, 3, 18-20.
   5  Polak, J.; Lu, B.C.Y., Can. J. Chem. 1973, 51, 4018-23.
   6  Price, L.C., Am. Assoc. Petrol. Geol. Bull. 1976, 60, 213-44.
   7  Krzyzanowska, T.; Szeliga, J., Nafta (Katowice) 1978, 12, 413-7.