Ultrasonic and sonochemical reaction studies of O -Cresols in different solvent mixtures.

Ultrasonic and sonochemical reaction studies have been carried out by measuring ultrasonic velocities (ν) in the mixing of phenols like ortho -cresol with esters like ethyl acetate and iso amyl acetate as solvents. The ultrasonic velocities (ν) were measured using ultrasonic pulse echo overlap technique (model UX4400-M) on mixing of o -cresol with solvents at different temperatures. The results are interesting because increase in the acid content in the binary mixture decreases the ultrasonic velocity (ν). Another important feature is the effect of solvents like isoamyl acetate instead of ethyl acetate on the kinetic process. The reaction rate is larger with ethyl acetate as compared to the kinetic rate in isoamyl acetate. The variation of ultrasonic velocity (ν) in the binary mixtures of o -cresol–isoamyl acetate system with sonic waves is also studied and it has been found that the reaction rate decreases due to the passage of sonic waves through the medium. Arrhenious parameters have been computed for o -cresol–isoamyl acetate system. The free energy of activation (Δ F    # ) has been computed for o -cresol–ethyl acetate system. It is found that heat of activation ( E a ), entropy of activation (Δ S    # ) and free energy of activation (Δ F    # ) are quite in order for this process. [ABSTRACT FROM AUTHOR]