Nitrous acid

2), a weak 2 is obtained when dinitrogen trioxide (N 2 3) is added to 2 by adding acid to a solution of a nitrite. NO 2 − + H 3O + → HNO 2 + H 2O It decomposes slowly at room temperature—and more rapidly at elevated temperatures—to 2, is an important example of a NaNO 3 + Pb → NaNO 2 + PbO This salt is added to meats, such as hot dogs, for two reasons. It prolongs the meat’s retention of a red colour, and it inhibits the growth of In general, the salts of all oxyacids are more stable than the acids themselves; such is the case with nitrites. They are much more stable than nitrous acid. Most nitrites are soluble in water and in concentrated forms, like nitrates, can explode upon heating or detonation. Oxyacids of phosphorus Orthophosphoric acid, H 3PO 4, is usually called simply 3PO 4 is produced by 4O 10) in water, although it is more commonly prepared by treating calcium phosphate, Ca 3(PO 4) 2, with concentrated 2SO 4. Ca 3(PO 4) 2 + 3H 2SO 4 → 2H 3PO 4 + 3CaSO 4 The products are diluted with water, and the insoluble CaSO 4 is removed by filtration. The dilute acid produced is contaminated with calcium dihydrogen 2PO 4) 2, and other compounds found with naturally occurring Ca 3(PO 4) 2. Orthophosphoric acid is a triprotic acid—i.e., it can donate all three of its 2PO 4 − ion; hydrogen phosphates, containing the HPO 4 2− ion; and orthophosphates, containing the PO 4 3− 2PO 4 − is a weak acid. Aqueous solutions of hydrogen phosphates are basic, because the HPO 4 2− ion is ...

Reaction with Primary Aliphatic and Aromatic Amines Primary aliphatic and aromatic amines react with nitrous acid forming arena diazonium salts while the reaction of secondary amines gives N-nitrosamines (R 2NN=O). Now, let’s take a closer look and see how this happens starting with the formation of arena diazonium salts. Nitrous acid does not direclty react with the amino group. It is a very unstable acid and therefore, the reaction is carried out with sodium nitrite (NaNO 2) which decompose to form nitrous acid under acidic conditions. The reactive species in both reactions is the extremely electrophilic nitrosonium ion or nitrosyl cation ( +NO), formed in situ from sodium nitrite reacting with a strong acid, such as HCl or H 2SO 4: The nitrosonium ion is formed in low concentrations and immediately reacts with the amine present in the reaction mixture thus shifting the equilibrium of this initial step forward. This reaction is called diazotization and begins with nucleophilic attack of the amine on the nitrosonium ion followed by deprotonation. After a proton transfer, an N-nitrosamine is generated which is eventually converted into a diazonium salt by loss of H 2O: Below is the summary of arene diazonium salt reactions and more details can be found in Primary alkyl diazonium salts, on the other hand, are not of great interest since they are very unstable below room temperature forming carbocations with loss of N 2. The various substitution and elimination reactions are...

Nitric acid is used for the production of ammonium nitrate, a major component of fertilizers. It is also used for producing explosives like nitroglycerin and trinitrotoluene (TNT) and for oxidizing metals. nitric acid, (HNO 3), colourless, fuming, and highly corrosive The preparation and use of nitric acid were known to the early

Nitrous Acid Nitrous acid/nitrite can also be oxidized in the aqueous solutions found in the atmosphere in the form of fogs, clouds, and particles. From: Chemistry of the Upper and Lower Atmosphere, 2000 Related terms: • Science and Technology • Methane • Sludge • Pretreatment • Denitrification • Nitrification • Nitrite • Nitrogen Monoxide • Dissolved Oxygen Markus W. Sigrist, ... Tibor Ajtai, in Advances in Spectroscopic Monitoring of the Atmosphere, 2021 5.1.5.6QEPAS study on short-lived species Nitrous acid in the gas phase (HONO) plays a crucial role in the atmospheric oxidation capacity and thus for the regional air quality and global climate change ( Finlayson-Pitts and Pitts, 2000; Stemmler et al., 2006; Stutz et al., 2013). However, due to the chemically reactive species (atmospheric lifetime of 10–20min) and low concentrations in the few ppb range, its measurement is challenging. As a result, the sources and sinks of HONO as well as their formation mechanism in the atmosphere are still not completely defined and understood. In this respect, QEPAS represents a very valuable option as it is a highly sensitive technique which requires only a small sampling volume resulting in a short residence time. Yi et al. (2015) designed a so-called off-axis QEPAS cell ( Liu et al., 2009) with a total volume of 40mm 3 containing the TF and a microresonator tube of 0.8mm diameter and 5.8mm length. The gas residence time in this cell amounts to less than 10ms. The beam of a CW EC-Q...