Dinitrogen trioxide

Dinitrogen trioxide
Dinitrogen trioxide resonance hybrid
Dinitrogen trioxide is blue
Names
IUPAC name
N-Oxonitramide[1]
Other names
  • Nitrous anhydride
  • Nitrogen sesquioxide
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.031.013 Edit this at Wikidata
EC Number
  • 234-128-5
UNII
UN number 2421
  • InChI=1S/N2O3/c3-1-2(4)5 checkY
    Key: LZDSILRDTDCIQT-UHFFFAOYSA-N checkY
  • InChI=1/N2O3/c3-1-2(4)5
    Key: LZDSILRDTDCIQT-UHFFFAOYAC
  • [O-][N+](=O)N=O
Properties
N2O3
Molar mass 76.011 g·mol−1
Appearance Deep blue liquid
Density
  • 1.447 g/cm3, liquid
  • 1.783 g/cm3, gas
Melting point −100.7[2] °C (−149.3 °F; 172.5 K)
Boiling point 3.5 °C (38.3 °F; 276.6 K) (dissociates[2])
reacts to form nitrous acid
Solubility soluble in ether
−16.0·10−6 cm3/mol
Structure
planar, Cs
2.122 D
Thermochemistry
65.3 J/(mol·K)
314.63 J/(mol·K)
91.20 kJ/mol
Hazards
GHS labelling:[3]
GHS03: OxidizingGHS05: CorrosiveGHS06: Toxic
Danger
H270, H310+H330, H314
P220, P244, P260, P262, P264, P270, P271, P280, P284, P301+P330+P331, P302+P350, P303+P361+P353, P304+P340, P305+P351+P338, P310, P320, P321, P322, P361, P363, P370+P376, P403, P403+P233, P405, P410+P403, P501
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 4: Very short exposure could cause death or major residual injury. E.g. VX gasFlammability 0: Will not burn. E.g. waterInstability 2: Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water. E.g. white phosphorusSpecial hazard OX: Oxidizer. E.g. potassium perchlorate
4
0
2
OX
Flash point Non-flammable
Related compounds
Related compounds
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Dinitrogen trioxide (also known as nitrous anhydride) is the inorganic compound with the formula N2O3. It is a nitrogen oxide. It forms upon mixing equal parts of nitric oxide and nitrogen dioxide and cooling the mixture below −21 °C (−6 °F):[4]

•
NO + •
NO
2 ⇌ N
2O
3

Dinitrogen trioxide is only isolable at low temperatures (i.e., in the liquid and solid phases). In liquid and solid states, it has a deep blue color.[2] At higher temperatures the equilibrium favors the constituent gases, with KD = 193 kPa (25 °C).[5][clarification needed]

This compound is sometimes called "nitrogen trioxide", but this name properly refers to another compound, the (uncharged) nitrate radical •NO3.

  1. ^ "Dinitrogen trioxide".
  2. ^ a b c Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 444. ISBN 978-0-08-037941-8.
  3. ^ "Dinitrogen trioxide". pubchem.ncbi.nlm.nih.gov. Retrieved 23 December 2021.
  4. ^ Greenwood, Norman N.; Earnshaw, Alan (1984). Chemistry of the Elements. Oxford: Pergamon Press. pp. 521–22. ISBN 978-0-08-022057-4.
  5. ^ Holleman, Arnold Frederik; Wiberg, Egon (2001), Wiberg, Nils (ed.), Inorganic Chemistry, translated by Eagleson, Mary; Brewer, William, San Diego/Berlin: Academic Press/De Gruyter, ISBN 0-12-352651-5