What is the ∆G for the following reaction under nonstandard conditions for the formation of NH4NO3(s)?. 2NH3(g) + 2O2(g)NH4NO3(s) + H2O(l). Given:. NH4NO3: ∆Hf = -365.56 kJ ∆Sf = 151.08. NH3: ∆Hf = -46.11 kJ ∆Sf = 192.45. H2O: ∆Hf = -285.830 kJ ∆Sf = 69.91