US EPA

7451033 

Journal Article 

Heat Capacity, Enthalpy of Formation, and Entropy of Methyl Carbamate 

Zeng, Z; Li, X; Xue, W; Zhang, CS; Bian, S 

2010 

Yes 

Industrial and Engineering Chemistry Research
ISSN: 0888-5885
EISSN: 1520-5045 

49 

12 

5543-5548 

English 

10.1021/ie9014342 

WOS:000278416800009 

The heat capacity (Cp) of methyl carbamate (MC) was measured with an adiabatic calorimeter. The standard enthalpy of formation (ΔfH0(cr, 298.15 K)) and the standard entropy (S0(cr, 298.15 K)) for MC were determined. Thus, Cp(T) values of MC were obtained for the crystal and liquid forms in the temperature range of 298.15-433.10 K. A quadratic trinomial was used to correlate the data of Cp(T). The enthalpy of fusion of MC was measured using differential scanning calorimetry (DSC), and its sublimation enthalpy was estimated. The gas-phase standard enthalpy of formation (Δ fH0(g, 298.15 K)) of MC was calculated via the method of group contribution developed by Benson. Based on the above data, the values of ΔfH0(cr, 298.15 K) and S0(cr, 298.15 K) of MC were estimated to be-513.57 kJ/mol and 77.1 J mol-1 K -1, respectively. A thermochemical cycle including a reversible reaction was designed to examine the reliability of the estimated values by measuring the equilibrium constant of the reaction. The results showed that the estimated values for MC were acceptable. © 2010 American Chemical Society. 

Adiabatic calorimeters; Enthalpy of formation; Enthalpy of fusion; Gas-phase standard; Group contributions; Heat capacities; Methyl carbamate; Reversible reaction; Standard enthalpy of formation; Standard entropy; Sublimation enthalpy; Temperature range; Thermochemical cycles; Differential scanning calorimetry; Equilibrium constants; Specific heat; Standards; Enthalpy