Calculate δ h ∘ in kilojoules for the reaction of ammonia (δ h ∘ f =−46.1 kj/mol) with o 2 to yield nitric oxide no (δ h ∘ f =91.3 kj/mol) and h 2 o(g) (δ h ∘ f =−241.8 kj/mol) , a step in the ostwald process for the commercial production of nitric acid.