What is "dinitrogen trioxide"

n. (context inorganic compound English) The binary compound of nitrogen and oxygen N₂O₃, a pale blue liquid that reacts with water to form nitrous acid.

Dinitrogen trioxide is the chemical compound with the formula NO. This deep blue solid is one of the binary nitrogen oxides. It forms upon mixing equal parts of nitric oxide and nitrogen dioxide and cooling the mixture below −21 °C (−6 °F):

Dinitrogen trioxide is only isolable at low temperatures, i.e. in the liquid and solid phases. At higher temperatures the equilibrium favors the constituent gases, with K = 193 kPa (25 °C).