Phase equilibrium and critical properties of the system $[x\mathrm{H}_2\mathrm{O} + (1 - x)\mathrm{C}_7\mathrm{H}_{16}]{,}\,\,x = 0.355$ mol fraction

An automated, experimental setup based on a high-temperature, adiabatic calorimeter-piezometer was used to study the temperature dependence of the isochoric-heat capacity of a double stratified system of n-heptane–water with a water content of $x = 0.355$ mol fraction in a density range of $149.9$–$399.8$ kg/m$^3$ at temperatures of $397.15$–$550.15$ K. This includes the phase-transition regions and the critical region. The critical system parameters and the parameters of azeotrope formation are determined.