question_answer

Standard heat of combustion of \[{{C}_{2}}{{H}_{2}}\,\left( g \right)\] and \[{{C}_{2}}{{H}_{4}}\,\,\left( g \right)\] are - 310.6 kcal and - 337.2 kcal per mole respectively. Heat of formation of water is\[-\,68.3\text{ }kcal\text{ }mo{{l}^{-\,1}}\]. Calculate heat of hydrogenation of \[{{C}_{2}}{{H}_{2\text{ }}}\,\left( g \right)\,\,to\,\,{{C}_{2}}{{H}_{4}}\,\left( g \right).\]  

Answer:

-41.70