Vapor Pressure,Vaporization Enthalpy,Standard Enthalpy of Formation and Standard Entropy of n-Butyl Carbamate

The vapor pressures of n-butyl carbamate were measured in the temperature range from 372.37 K to 479.27 K and fitted with Antoine equation. The compressibility factor of the vapor was calculated with the Virial equation and the second virial coefficient was determined by the Vetere model. Then the standard enthalpy of vaporization for n-butyl carbamate was estimated. The heat capacity was measured for the solid state (299.39-324.2 K) and liquid state (336.65-453.21 K) by means of adiabatic calorimeter. The standard enthalpy of formation Δ_fH^?crystal (cr),298.15 K] and standard entropy S^?(crystal,298.15 K) of the substance were calculated on the basis of the gas-phase standard enthalpy of formation Δ_fH^?(g,298.15 K) and gas-phase standard entropy S^?(g,298.15 K), which were estimated by the Bensonmethod. The results are acceptable, validated by a thermochemical cycle.