| IUPAC name
| Other names
|Molar mass||30.01 g/mol|
|Melting point||−164 °C (−263 °F; 109 K)|
|Boiling point||−152 °C (−242 °F; 121 K)|
| 0.0098 g/100 ml (0 °C)|
0.0056 g/100 ml (20 °C)
|Solubility||Soluble in carbon disulfide|
|Solubility in ethanol||26.6 ml/100 ml|
|Solubility in sulfuric acid||3.4 ml/100 ml|
|Vapor pressure||26000 mmHg at 20 °C|
Std enthalpy of
|Safety data sheet||Sigma-Aldrich|
|Lethal dose or concentration (LD, LC):|
LC50 (Median concentration)
| 315 ppm (rabbit, 15 min)|
854 ppm (rat, 4 hr)
320 ppm (mouse)
| Nitrous oxide|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Nitric oxide (also known as nitrogen oxide or nitrogen monoxide) is a molecular, chemical compound with chemical formula of ·NO (also written as ·NO). Nitric oxide is a free radical—i.e., its bonding structure includes an unpaired electron, represented by the dot (·) on the nitrogen atom.
Nitric oxide oxidizes in air to give nitrogen dioxide.
- NO + ½ O2 → NO2
Nitric oxide is a colorless gas, almost insoluble in water.
Nitric oxide is sold by chemical suppliers in gas cylinders, though it's difficult for the amateur chemist to acquire this compound.
- 4 NH3 + 5 O2 → 4 ·NO + 6 H2O
- 8 HNO3 + 3 Cu → 3 Cu(NO3)2 + 4 H2O + 2 ·NO
If this reaction occurs in the presence of air, the resulting nitric acid will react with oxygen to give the brown nitrogen dioxide. If concentrated nitric acid is used, nitrogen dioxide will also be formed as side product.
- 2 NaNO2 + 2 NaI + 2 H2SO4 → I2 + 4 NaHSO4 + 2 ·NO
- 2 NaNO2 + 2 FeSO4 + 3 H2SO4 → Fe2(SO4)3 + 2 NaHSO4 + 2 H2O + 2 ·NO
- 3 KNO2(l) + KNO3(l) + Cr2O3(s) → 2 K2CrO4(s) + 4 NO(g)
- Make nitrous oxide
- Make metal nitrosyls
Nitric oxide will convert to nitrogen dioxide when exposed to air.
Nitric oxide tanks should be kept in a cold place, away from light and heat.
Can be neutralized by bubbling it in a sodium percarbonate solution.