| IUPAC name
| Other names
|Molar mass||92.011 g/mol|
|Appearance||Colorless liquid/Orange gas|
|Density||1.44246 g/cm3 (liquid, 21 °C)|
|Melting point||−11.2 °C (11.8 °F; 261.9 K) (decomposes to NO2)|
|Boiling point||21.69 °C (71.04 °F; 294.84 K)|
|Vapor pressure||96 kPa (20 °C)|
Std enthalpy of
|Safety data sheet||SolGroup|
| Nitrous oxide|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Dinitrogen tetroxide is the chemical compound N2O4. It is a useful reagent in chemical synthesis. It forms an equilibrium mixture with nitrogen dioxide.
Dinitrogen tetroxide exists in equilibrium with nitrogen dioxide:
- N2O4 ⇌ 2 NO2
Higher temperatures push the equilibrium towards nitrogen dioxide.
Dinitrogen teroxide is a colorless liquid, sometimes reddish-brown, which reacts violently with water. It has an acrid unpleasant odor, reminiscent of car smog.
Unlike NO2, N2O4 is diamagnetic since it has no unpaired electrons.
Dinitrogen tetraoxide is available as liquid, but only for industrial entities.
Condensation of nitrogen dioxide at low temperatures will yield dinitrogen tetraoxide. The process is reversible.
- Make nitrogen dioxide
- Make anhydrous nitrate salts
Dinitrogen tetroxide is highly corrosive and toxic. Contact with certain chemicals, like hydrazine will result in ignition.
At low temperatures. Do not store it for long.
Can be neutralized by slowly dissolving it in a large volume of water, followed by neutralization with a base.