Ammonium nitrite

Ammonium nitrite
Identifiers
CAS number	13446-48-5 Y
ChemSpider	24223 Y
Jmol-3D images	Image 1
SMILES [O-]N=O.[NH4+]
InChI InChI=1S/HNO2.H3N/c2-1-3;/h(H,2,3);1H3 Y Key: CAMXVZOXBADHNJ-UHFFFAOYSA-N Y InChI=1/HNO2.H3N/c2-1-3;/h(H,2,3);1H3 Key: CAMXVZOXBADHNJ-UHFFFAOYAU
Properties
Molecular formula	NH4NO2
Molar mass	64.06 g/mol
Appearance	pale yellow crystals, slowly decomposes to nitrogen and water
Y nitrite (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Ammonium nitrite, NH₄NO₂, is the ammonia salt of nitrous acid. It is used as a rodenticide, microbiocide and agricultural pesticide, and is acutely toxic to both humans and aquatic organisms.^[1]

Preparation

Ammonium nitrite forms naturally in the air and can be prepared by the absorption of equal parts nitrogen dioxide and nitric oxide upon aqueous ammonia.^[2]

It can also be prepared 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 and decompose on heating or in the presence of acid, with the formation of nitrogen.^[3] 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 explosion. It is desirable to maintain pH by adding Ammonia solution. The mole ratio of Ammonium Nitrite to Ammonia must be above 10% mole ratio.

NH₄NO₂ → N₂ + 2 H₂O

Properties

Ammonium nitrite may explode at a temperature of 60-70 °C.^[2] It decomposes more quickly when a concentrated solution than when it is a dry crystal.

References

1. ^ "Ammonium nitrite - Identification, toxicity, use, water pollution potential, ecological toxicity and regulatory information". PAN Pesticides Database - Chemicals. http://www.pesticideinfo.org/Detail_Chemical.jsp?Rec_Id=PC37098. Retrieved 2006-07-26. 
2. ^ ^{a b} Thomas Scott; Mary Eagleson (1994). Concise encyclopedia chemistry. Walter de Gruyter. p. 66. ISBN 3110114518. 
3. ^ "VIAS Encyclopedia: Ammonium Nitrite". http://www.vias.org/encyclopedia/chem_ammonia_salts_no2.html.