Nitrogen oxide

Nitrogen oxide may refer to a binary compound of oxygen and nitrogen, or a mixture of such compounds:

Charge-neutral

 * Nitric oxide (NO), nitrogen(II) oxide, or nitrogen monoxide
 * Nitrogen dioxide (NO2), nitrogen(IV) oxide
 * Nitrogen trioxide (NO3), or nitrate radical
 * Nitrous oxide (N2O), nitrogen(0,II) oxide
 * Dinitrogen dioxide (N2O2), nitrogen(II) oxide dimer
 * Dinitrogen trioxide (N2O3), nitrogen(II,IV) oxide
 * Dinitrogen tetroxide (N2O4), nitrogen(IV) oxide dimer
 * Dinitrogen pentoxide (N2O5), nitrogen(V) oxide, or nitronium nitrate [NO2]+[NO3]−
 * Nitrosyl azide (N4O), nitrogen(−I,0,I,II) oxide
 * Nitryl azide (N4O2)
 * Oxatetrazole (N4O)
 * Trinitramide (N(NO2)3 or N4O6), nitrogen(0,IV) oxide

Cations

 * Nitrosonium (N\tO+ or [NO]+)
 * Nitronium (O\dN+\dO or [NO2]+)

Atmospheric sciences
In atmospheric chemistry:
 * NO_{x} (or NOx) refers to the sum of NO and NO2.
 * NO_{y} (or NOy) refers to the sum of NO_{x} and all oxidized atmospheric odd-nitrogen species (e.g. the sum of NO_{x}, HNO3, HNO2, etc.)
 * NO_{z} (or NOz) = NO_{y} − NO_{x}


 * Mixed Oxides of Nitrogen ("MON"): solutions of nitric oxide in dinitrogen tetroxide/nitrogen dioxide.

Stability
Due to relatively weak N–O bonding, all nitrogen oxides are unstable with respect to N2 and O2, which is the principle behind the catalytic converter, and prevents the oxygen and nitrogen in the atmosphere from combusting.