Nitric acid is made by the oxidation of ammonia. In the first stage, ammonia is reacted with oxygen while a catalyst is present, so that nitrogen monoxide is formed. $4\text{NH}_3(g) + 5\text{O}_2(g) \rightleftharpoons 4\text{NO}(g) + 6\text{H}_2\text{O}(g) \quad \Delta H = -1636\ \text{kJ mol}^{-1}$ Which combination of conditions would give the highest equilibrium yield of nitrogen monoxide?
- Ahigh temperature, high pressure
- Bhigh temperature, low pressure
- Clow temperature, high pressure
- Dlow temperature, low pressure