Isochoric heat capacity and liquid‐gas coexistence curve of carbon dioxide in the region of the immediate vicinity of the critical point

Abstract

Listen

Translate article

AbstractThe paper contains the results of new experimental measurements of the isochoric heat capacity and the liquid‐gas coexistence curve of carbon dioxide in the one‐phase region near the critical point. The measurements were performed in a high temperature adiabatic calorimeter used earlier for the determination of the isochoric heat capacity of several liquids and liquid mixtures near the critical points [1, 2].The experiments have been performed at seven isochores, namely: 461.2, 464.5, 467.5, 470.1, 477.7, 499.0, and 509.8 kg·m−3 in the neighbourhood of the critical point and the coexistence curve. The measurements were made with samples of constant mass contained in a calorimeter vessel of nearly constant volume. Uncertainties of the heat‐capacity measurements are estimated to be less than 2 percent far from Tc and 3 percent in the immediate vicinity of the critical point. The uncertainty in temperature was less than ±10 mK.