Kinetics and Thermodynamics of Solvent Evaporation

A series of experiments that combine blend kinetic with thermodynamic parameters is outlined. From the simple measurements made over a 60 minutes time scale, students graph and examine over a dozen chemical and physical correlations. In this exercise, students measure the evaporation rates of water-methanol mixtures for sixty minutes using a balance. The evaporation rate (g/min or mL/min) is correlated with parameters taken from the literature such as the heat of evaporation, surface tension and viscosity. The lab can be adapted to a number of chemistry courses.