The rate of evaporation of droplets. III. Vapour pressures and rates of evaporation of straight-chain paraffin hydrocarbons

Abstract

Abstract The vapour pressures, latent heats of vaporization and fusion and diffusion coefficients of the vapours in air, have been determined at 15 to 40° C, by a combination of Knudsen’s vapour-pressure technique and studies on the rate of evaporation of drops and solid beads, for n-C16H34, n-C17H36 and n-C18H38. The rates of evaporation of drops and solid beads agree with the previously published theory, and lead to a value of unity for the evaporation coefficient. A new experimental method is described for determining the self-cooling on evaporation of a drop. The bearing of the results on the size and shape of hydrocarbon molecules is discussed.