Search results
Results from the WOW.Com Content Network
Nitric acid is an inorganic compound with the formula H N O 3.It is a highly corrosive mineral acid. [6] The compound is colorless, but samples tend to acquire a yellow cast over time due to decomposition into oxides of nitrogen.
The nitrate anion is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a formal charge of −1.
Dinitrogen pentoxide (also known as nitrogen pentoxide or nitric anhydride) is the chemical compound with the formula N 2 O 5. It is one of the binary nitrogen oxides, a family of compounds that contain only nitrogen and oxygen. It exists as colourless crystals that sublime slightly above room temperature, yielding a colorless gas. [4]
Nitrous acid (molecular formula H N O 2) is a weak and monoprotic acid known only in solution, in the gas phase, and in the form of nitrite (NO − 2) salts. [3] It was discovered by Carl Wilhelm Scheele, who called it "phlogisticated acid of niter". Nitrous acid is used to make diazonium salts from amines.
In the United States of America, over seven million tonnes of nitric acid are produced every year, most of which is used for nitrate production for fertilisers and explosives, among other uses. Anhydrous nitric acid may be made by distilling concentrated nitric acid with phosphorus pentoxide at low pressure in glass apparatus in the dark.
Nitric acid is a source of nitric oxide complexes, although the details are obscure. Probably relevant is the conventional self-dehydration of nitric acid: 2 HNO 3 → NO 2 + NO 3 − + H 2 O. Nitric acid is used in some preparations of nitroprusside from ferrocyanide: HNO 3 + [Fe(CN) 6] 4-→ [Fe(CN) 5 (NO)] 2-+ OH − + OCN −
The nitronium ion, [N O 2] +, is a cation.It is an onium ion because its nitrogen atom has +1 charge, similar to ammonium ion [NH 4] +.It is created by the removal of an electron from the paramagnetic nitrogen dioxide molecule NO 2, or the protonation of nitric acid HNO 3 (with removal of H 2 O).
This reaction is the first step in the production of nitric acid: [13] 4 NH 3 + 7 O 2 → 4 NO 2 + 6 H 2 O. It can also be produced by the oxidation of nitrosyl chloride: 2 NOCl + O 2 → 2NO 2 + Cl 2. Instead, most laboratory syntheses stabilize and then heat the nitric acid to accelerate the decomposition.