Comment
Figure shows the first heating process. Sulfidation reaction starts at 560�Ž, and continues till 660�Ž. Exothermic peak at 593�Ž.�@Total enthalpy of reaction, ƒ¢H‚’=817.6J/g.
The enthalpy of formation
�@Product is the mixture of Si + SiS2. Corresponding XRD pattern is given in figure. Based on the reaction equation of 2Si+2S=SiS2+Si, the enthalpy becomes ƒ¢Hf=30.5Kcal/mol.