Thermodynamic Properties of Trifluoroacetonitrile from 12°K to Its Boiling Point

Abstract

The saturated heat capacities of trifluoroacetonitrile have been measured from 12°K to the normal boiling point 205.47°K. The vapor pressure of the liquid to 1 atm is represented by the equation log10Pmm=−1337.916/T−4.02312 log10T+18.69693.The solid-liquid-vapor triple-point temperature is 128.73°K. The heat of fusion at the triple point and the heat of vaporization at the normal boiling point are, respectively, 1187.7 cal/mole and 4262 cal/mole. The experimental value of the entropy of the gas at the normal boiling point, 65.01±0.20 eu/mole, is in excellent agreement with the theoretical value of 64.96 eu/mole calculated from spectroscopic and molecular data assuming a symmetrical top molecule.