| IUPAC name
| Systematic IUPAC name
| Other names
Nitrous acid, ammonium salt
|Colorless to pale yellow solid
|32–33 °C (90–91 °F; 305–306 K)
|Reacts with acids
|Safety data sheet
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Ammonium nitrite is an inorganic chemical compound, the ammonia salt of nitrous acid, with the formula NH4NO2. It is not used in pure isolated form, since it is highly unstable and decomposes into water and nitrogen even at room temperature.
Ammonium nitrite decomposes even at room temperature to release nitrogen gas.
- NH4NO2 → N2 + 2 H2O
Concentrated ammonium nitrite will explode if heated too strong.
Ammonium nitrite is an unstable yellow to colorless solid, soluble in water.
Ammonium nitrite explodes if heated above 60–70 °C, and will decompose quicker when dissolved in a concentrated aqueous solution, than in the form of a dry crystal.
Ammonium nitrite is extremely difficult to find, and almost no big chemical supplier has it in their stock.
One supplier sells a 20% aq. solution of this compound.
Adding ammonium sulfate to barium or lead(II) nitrite will precipitate their respective sulfates, while leaving ammonium nitrite in solution. The reaction between silver nitrite and ammonium chloride will work in the same way.
The resulting ammonium nitrite obtained is in aqueous form. Heating the solution to dry the compound will cause it to decompose and high concentrations it may explode. To obtain the solid compound, you will have to cool the solution until the ammonium nitrite precipitates out of the solution. To limit decomposition, you will have to maintain its pH above 7, which can be easily done by adding an excess of ammonia. Careful vacuum drying may be used to dry the compound at room temperature, but this is very dangerous.
- Make nitrogen gas
- Synthesis of ammonium cobalti-nitrite
- Make hydroxylamine
Ammonium nitrite is unstable and heating it may cause it to explode.
It is not stable to store this compound in pure form, while aqueous solutions should not be stored for long periods of time. Keep them at high pH and at low temperatures.
Can be easily neutralized by strongly diluting the compound in water, then adding a base like sodium hydroxide or sodium percarbonate, though ammonia will be released from the neutralization. Do not add acid to neutralize the ammonia, as the leftover ammonium nitrite may decompose violently.