"Nitric acid (HNO3) is an extremely important chemical used in the manufacture of fertilisers and explosives. It is made from ammonia by the Ostwald Process which was developed in 1902 by the German chemist Wilhelm Ostwald (below, left), who got the Nobel prize for Chemistry in 1909. This process reacts together O2 and ammonia NH3 at 850°C and 5 atmospheres pressure, with the help of platinum and rhodium catalysts, to make NO gas. This is then oxidised to NO2, which is then dissolved in water to make HNO3."