Microcalorimetric determination of the enthalpy of sublimation of benzoic acid and anthracene

Abstract

A Calvet microcalorimeter has been utilized to determine the sublimation enthalpy of benzoic acid and anthracene. The vapor pressures measured by Knudsen effusion weight‐loss method over the temperature ranges 338–383°K and 353–432°K were, respectively, ${\log }_{10}{p}_{(\mathrm{torr})}\text{=(12.175 ± 0.047) − (4501 ± 17)/T}$ , for benzoic acid, and ${\log }_{10}{p}_{(\mathrm{torr})}\text{=(12.616 ± 0.062) − (5277 ± 24)/T}$ , for anthracene. The Gibbs energy functions for C₆H₅COOH and C₁₄H₁₀ gaseous molecules have been estimated.