The equilibrium constants K for the reactions (1-phenyl-1-alkanone + 2-propanol = 1-phenyl-1-alkanol + acetone) in the solvents n-pentane and n-hexane have been determined by using gas chromatography at the temperature 298.15 K. The 1-phenyl-1-alkaones included in this study were: 1-phenyl-1-ethanone, 1-phenyl-1-propanone, 1-phenyl-1-butanone, 1-phenyl-1-pentanone, 1-phenyl-1-hexanone, and I-phenyl-l-heptanone. The equilibrium constants for the reaction involving I-phenyl-l-ethanone were measured in the solvent n-hexane as a function of temperature (288 K to 308 K). The calculated thermodynamic quantities for the 1-phenyl-1-ethanone reaction at T = 298.15 K are: K = 0.2177 +/- 0.0018; the standard molar Gibbs free energy change, Delta(r)G(m)degrees = (3.78 +/- 10.02) kJ center dot mol(-1), the standard molar enthalpy change, Delta H-r(m)degrees = (4.53 +/- 0.87) kJ center dot mol(-1), and the standard molar entropy change, Delta S-r(m)degrees = (2.5 +/- 2.9) J center dot K-1 center dot mol(-1). The equilibrium constants of 1-phenyl-1-alkanone with an odd number of carbons in alkyl side chain are higher than the equilibrium constants of the preceding 1-phenyl-1-alkanone having an even number of carbons in the side chain and follow a zig-zag pattern with increasing carbon number in the alkyl side chain. (c) 2006 Elsevier Ltd. All rights reserved.