The heat capacity of liquid carbon disulfide + acetonitrile, especially near the upper critical solution temperature

Abstract

The heat capacity C_p of the binary liquid system CS₂ + CH₃CN has been studied. This system has an upper critical solution temperature T₀ ≈ 323.4 K and a critical mole fraction of CS₂x₀ ≈ 0.5920. Measurements were made both for mixtures close to and far away from the critical region. The heat capacity of the mixture with x = x₀ exhibits a symmetric logarithmic anomaly around T_c, which is apparently preserved even for compositions in the immediate vicinity of x_c. For compositions far away from x_c, only a normal rise in C_p over the covered temperature range is observed.