Question

Calculate the enthalpy of reaction from the standard enthalpies of formation of the reactant and product molecules.

2C2H6+7O2-->4CO2+6H20

I am using the back of my book for the standard enthalpies of formation, but cannot seem to find the HoF for C2H6?

Answer 1

My book lists -84.86 kJ/mol for the gas.

Answer 2

Calculate the enthalpy change for the reaction

NO(g) + O(g) --> NO2(g)

from the following data:

NO(g) + O3(g) --> NO2(g) + O2(g) ; ∆H = -198.9 kJ
O3(g) --> 1.5O2(g) ; ∆H = -142.3 kJ
O2(g) --> 2O(g) ; ∆H = 495.0 kJ