Excess molar enthalpies and excess molar volumes for the binary mixtures of 2-methylpropane, 2-methylpropene, and propan-2-ol at the temperatures (298.15 and 323.15) K and the pressures (5, 10, and 15) MPa

✍ Scribed by J.D. Moore; P.R. Brown; J.B. Ott

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 306 KB
• Volume: 29
• Category: Article
• ISSN: 0021-9614
• DOI: 10.1006/jcht.1996.0147

✦ Synopsis

Excess molar enthalpies H E m and excess molar volumes V E m have been determined for (2-methylpropane + 2-methylpropene), (2-methylpropane + propan-2-ol), and (2-methylpropene +propan-2-ol) at the temperatures (298.15 and 323.15) K and at the pressures (5, 10, and 15) MPa. For (alkane + alkene), H E m and V E m are small and positive for all values of mole fraction x of alkane, with small temperature and pressure coefficients. For (alkane + alkanol) and (alkene + alkanol), the H E m results and the excess molar heat capacity C E p,m are large and positive, while V E m (x) is s-shaped, changing from negative to positive with increasing mole fraction of the hydrocarbon. Pressure has a small effect on H E m for these systems, but affects V E m by decreasing the magnitudes of the positive and negative regions of the s-shaped curves and shifting the intersection with the abscissa (V E m = 0) to lower mole fraction of the alkane or alkene with increasing pressure. Comparisons are made among the three systems of the effect of the hydroxyl group and the double bond on H E m (x) and V E m (x). These systems are also compared with (n-alkane + n-alkanol) of similar molar masses.