posted by Lauren .
With a platinum catalyst, ammonia will burn in oxygen to give nitric oxide, NO.
4NH3 + 5O2 -----> 4NO + 6H2O
Delta H= -906 kJ
What is the enthalpy change for the following reaction?
NO + 3/2H2O ---> NH3 + 5/4O2
Note that if you divide all the cofficients by 4 you will have
NH3 + 5/4 O2 ==> NO + 3/2 H2O
so delta H for that reaction is what?    -906 kJ/4 ??
Then the reverse direction is just the negative of that.