6. The Ostwald process for the commercial production of nitric acid from ammonia and oxygen involves the following steps: 4NH3(g) + 5O2(g) → 4NO(g) + 6H2O(g)
2NO(g) + O2(g) → 2NO2(g)
3NO2(g) + H2O(l) → 2HNO3(aq) + NO(g). The values of ∆Hf o for some chemicals are the following: NO(g), 90 kJ/mol; H2O(g), -242 kJ/mol; NH3(g), -46 kJ/mol; NO2(g), 34 kJ/mol; HNO3(aq), -207 kJ/mol; H2O(l), -286 kJ/mol. Use the provided values of ∆Hf o to calculate the value of ∆Ho for the last reaction, 3NO2(g) + H2O(l) → 2HNO3(aq) + NO(g) to be . (A) -908 kJ (B)-112 kJ (C) -140 kJ (D) -826 kJ (E)-220 kJ