When 2mole of `C_(2)H_(6)` are completely burnt `3129kJ` of heat is liberated. Calculate the heat of formation of `C_(2)H_(6).Delta_(f)H^(Theta)` for `CO_(2)` and `H_(2)O` are `-395` and `-286kJ`, respectively.

When 2 moles of C_(2)H_(6)(g) are completely burnt 3120 kJ of heat is liberated. Calculate the enthyalpy of formation, of C_(2)H_(6)(g) . Given Delta_(f)H for CO_(2)(g) & H_(2)O(l) are -395 & -286 kJ respectively.

The standard enthalpy of formation of octane (C_(8)H_(18)) is -250kJ //mol . Calculate the enthalpy of combustion of C_(8)H_(18) . The enthalpy of formation of CO_(2)(g) and H_(2)O(l) are -394 kJ//mol and -286kJ//mol respectively.

The standard enthalpy of formation of octane (C_(8)H_(18)) is -250kJ //mol . Calculate the enthalpy of combustion of C_(8)H_(18) . The enthalpy of formation of CO_(2)(g) and H_(2)O(l) are -394 kJ//mol and -286kJ//mol respectively.

The standard enthalpy of formation of octane (C_(8)H_(18)) is -250kJ //mol . Calculate the enthalpy of combustion of C_(8)H_(18) . The enthalpy of CO_(2)(g) and H_(2)O(l) are -394 kJ//mol and -286kJ//mol respectively.

Calculate the heat of formation of benzene given that the standard heat of combustion of benzene is - 3266 kJ and standard heat of formation of CO_(2)(g) and H_(2)O(l) are - 393.1 kJ and - 286 kJ respectively.