W. Marczak, A. Heintz, M. Bucek
Jul 1, 2004
Citations
0
Influential Citations
18
Citations
Journal
The Journal of Chemical Thermodynamics
Abstract
Abstract Enthalpies of solution of methanol and 2-methyl-2-propanol ( tert -butanol) in pyridine and its methyl derivatives were investigated in the range of mole fractions of alcohol x ⩽0.02 at temperature 298.15 K by a titration calorimeter. Dissolution of methanol is an exothermic process, with heat effects very close to those for water reported in part I of this study. The negative enthalpy of solution increases in the following order: pyridine ortho effect. Methyl groups are probably too small to prevent the nitrogen atom in the pyridine ring from hydrogen bonding. However, spacious hydrocarbon group in 2-methyl-2-propanol molecule makes the bonding difficult for 2,6-dimethylpyridine and 2,4,6-trimethylpyridine, thus the number of O–H⋯N bonds is smaller than that in the solutions of methanol or water. The two latter seem to be very close to each other.