The Standard enthalpy of the reaction shown is 414 kJ/mol.
What is the enthalpy?
The relationship between enthalpy change, heat transfer, and work done in a system is described by the first law of thermodynamics. Enthalpy is particularly useful in studying and analyzing chemical and physical processes, especially those occurring at constant pressure.
For the reaction, the standard enthalpy is obtained from;
Enthalpy of products - Enthalpy of reactants
[(-400) + 6(-297) + 12(-92)] - [6(-246) + (-2224)]
-3286 - (-3700)
= 414 kJ/mol