Apparent Molar Volumes and Viscosities of Lauric, Palmitic, and Stearic Acids in 2-Butanol at (20, 30, 40, and 60) °C

Apparent molar volumes ( V ⌀ ) and viscosities of lauric, palmitic, and stearic acids as a function of concentration at (20, 30, 40, and 60) °C in 2-butanol are reported. The apparent molar volumes at infinite dilution ( ) were determined by extrapolating V ⌀ values to zero concentration. The variations of both and viscosity values with temperature and with chain length of fatty acid were examined. values were found to decrease with increasing temperature for all three fatty acids and to increase with increasing chain length of fatty acid at a constant temperature. Apparent molar expansivity data at infinite dilution ( ) were derived from the versus temperature data determined experimentally. values were negative, and their absolute values were found to increase with the chain length of fatty acid. The viscosities do not change appreciably with concentration at constant temperature while they do decrease considerably with temperature at a constant concentration. On the other hand, at a constant temperature and concentration, viscosities increased with increasing chain length.