Ammonium Nitrite - Wikipedia

Ammonium nitrite

Names
IUPAC name Ammonium nitrite
Identifiers
CAS Number	13446-48-5 Y
3D model (JSmol)	Interactive image
ChemSpider	24223 Y
ECHA InfoCard	100.033.257
EC Number	236-598-7
PubChem CID	26004
UNII	71ZQG69956
CompTox Dashboard (EPA)	DTXSID7065461
InChI InChI=1S/HNO2.H3N/c2-1-3;/h(H,2,3);1H3 YKey: CAMXVZOXBADHNJ-UHFFFAOYSA-N Y InChI=1/HNO2.H3N/c2-1-3;/h(H,2,3);1H3Key: CAMXVZOXBADHNJ-UHFFFAOYAU
SMILES [O-]N=O.[NH4+]
Properties
Chemical formula	[NH4]NO2
Molar mass	64.044 g·mol−1
Appearance	colorless or pale yellow crystals
Density	1.69 g/cm3
Melting point	Decomposes
Solubility in water	118.3 g / 100mL
Explosive data
Shock sensitivity	Low
Friction sensitivity	Low
Detonation velocity	>1000 m/s
Hazards
Occupational safety and health (OHS/OSH):
Main hazards	Explosive
GHS labelling:
Pictograms
Signal word	Danger
NFPA 704 (fire diamond)	2 0 3
Flash point	Non-flammable
Autoignitiontemperature	Non-flammable
Related compounds
Other anions	Ammonium nitrate
Other cations	Sodium nitrite
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Chemical compound

Ammonium nitrite is a chemical compound with the chemical formula [NH4]NO2. It is the ammonium salt of nitrous acid. It is composed of ammonium cations [NH4]+ and nitrite anions NO−2. It is not used in pure isolated form since it is highly unstable and decomposes into water and nitrogen, even at room temperature.

Preparation

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Ammonium nitrite forms naturally in the air and can be prepared by the absorption of equal parts nitrogen dioxide and nitric oxide in aqueous ammonia.[1]

It can also be synthesized by oxidizing ammonia with ozone or hydrogen peroxide, or in a precipitation reaction of barium or lead nitrite with ammonium sulfate, or silver nitrite with ammonium chloride, or ammonium perchlorate with potassium nitrite. The precipitate is filtered off and the solution concentrated. It forms colorless crystals which are soluble in water.

2 NH3 + O3 → [NH4]NO2 + H2O

Physical and chemical properties

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Ammonium nitrite may explode at a temperature of 60–70 °C,[1] and will decompose quicker when dissolved in a concentrated aqueous solution, than in the form of a dry crystal. Even in room temperature the compound slowly decomposes into water and nitrogen:

[NH4]NO2 → N2 + 2 H2O

It decomposes when heated or in the presence of acid into water and nitrogen.[2] Ammonium nitrite solution is stable at higher pH and lower temperature. If there is any decrease in pH lower than 7.0, it may lead to an explosion, since the nitrite can react to it. A safe pH can be maintained by adding an ammonia solution. The mole ratio of ammonium nitrite to ammonia must be above 10%.

References

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1. ^ a b Eagleson, Mary, ed. (1994). Concise Encyclopedia Chemistry. Translated by Eagleson, Mary. Translated and revised from ABC Chemie. Berlin: de Gruyter. p. 66. ISBN 0-89925-457-8.
2. ^ "VIAS Encyclopedia: Ammonium Nitrite".

v t e Ammonium salts
Inorganic salts	monatomic anions NH4F (NH4)2S NH4Cl (NH4)2Se NH4Br NH4I oxyanions NH4NO2 NH4NO3 CaNH4PO4 (NH4)2CO3 (NH4)4UO2(CO3)3 (NH4)HCO3 NH4H2AsO4 NH4BrO3 NH4ClO NH4OCN NH4B5O8 (NH4)3PO4 NH4PH2O2 (NH4)2HPO4 (NH4)H2PO4 NH4IO4 (NH4PO4)n(OH)2 NH4NaHPO4 (NH4)2SO3 (NH4)2SO4 (NH4)Al(SO4)2·12H2O (NH4)2Fe(SO4)2·6H2O NH4Fe(SO4)2·12H2O NH4SO3NH2 (NH4)HSO4 (NH4)2S2O8 (NH4)2S2O3 NH4ClO3 NH4ClO4 (NH4)2Mg(SO4)2 NH4VO3 Nd(NH4)2(NO3)5 (NH4)2CrO4 (NH4)2Cr2O7 NH4MnO4 (NH4)3AsO4 NH4BrO4 (NH4)2MoO4 (NH4)6Mo7O24 (NH4)3Mo12PO40 NH4IO3 (NH4)2Ce(NO3)6 (NH4)8Ce2(SO4)8·4H2O (NH4)10H2W12O42·4H2O NH4ReO4 (NH4)2SeO4 (NH4)2TeO4 other anions NH4BF4 NH4N3 NH4CN NH4[Au(CN)2] (NH4)HF2 (NH4)2SeBr6 (NH4)3AlF6 NH4SbF6 NH4AsF6 (NH4)3CrF6 (NH4)3FeF6 (NH4)3GaF6 (NH4)2GeF6 (NH4)3InF6 NH4NbF6 (NH4)2PtF6 (NH4)2ReF6 (NH4)2SnF6 NH4TaF6 (NH4)2UF6 (NH4)3VF6 (NH4)SiF6 (NH4)HS NH4SCN (NH4)2ZnCl4 (NH4)2MoS4 NH4I3 (NH4)2PtBr6 (NH4)2SnBr6 (NH4)2TeCl6 (NH4)2IrCl6 (NH4)2OsCl6 (NH4)2PtCl6 (NH4)2ReCl6 (NH4)2PdCl6 (NH4)2PbCl6 (NH4)3RhCl6 (NH4)2SeCl6 (NH4)2SnCl6 (NH4)4[Fe(CN)6] (NH4)3VS4 (NH4)2S5 (NH4)4[HgBr6] (NH4)2[PtI6] NH4AuCl4 (NH4)2PdCl4 (NH4)3AsS4 (NH4)2WS4 (NH4)2[PtCl4]
Organic salts	Aluminon Ammonium acetate Ammonium adipate Ammonium alginate Ammonium benzoate Ammonium bituminosulfonate Ammonium butyrate Ammonium carbamate Ammonium caprylate Ammonium cinnamate Ammonium citrate Ammonium diethyl dithiophosphate Ammonium ferric citrate Ammonium formate Ammonium fumarate Ammonium glutamate Ammonium heptadecanoate Ammonium itaconate Ammonium lactate Ammonium lauryl sulfate Ammonium laurate Ammonium malate Ammonium malonate Ammonium mandelate Ammonium myristate Ammonium nicotinate Ammonium nonanoate Ammonium oleate Ammonium oxalate Ammonium picrate Ammonium palmitate Ammonium perfluorononanoate Ammonium picolinate Ammonium propionate Ammonium salicylate Ammonium stearate Ammonium succinate Ammonium tartrate Ammonium thioglycolate Ammonium valerate Cupferron Ferric ammonium oxalate Murexide