Nitric Acid, a colorless, corrosive liquid that is also called aqua fortis (strong water). When exposed to light, it turns yellow. Nitric acid is a strong oxidizing agent. It is extremely reactive and will dissolve most metals. When mixed with hydrochloric acid it forms aqua regia, a liquid that will dissolve gold and platinum, metals that nitric acid alone cannot dissolve. Nitric acid can cause skin burns. The fumes of the acid are poisonous.

Nitric acid is produced commercially by burning ammonia (a compound of nitrogen and hydrogen) in the presence of a catalyst, a substance that aids a chemical reaction but is not affected by it. Two commercial grades of nitric acid are red fuming nitric acid, which is about 86 per cent pure nitric acid, and white fuming nitric acid, which is about 97.5 per cent pure. Nitric acid is used in the manufacture of dyes, fertilizers, plastics, nitrous oxide, nitro compounds, and explosives such as nitroglycerin and guncotton.

Chemical formula: HNO3.