Nitrogen (O2 free)

Nitrogen dioxide is the chemical compound with the formulaNO₂ it is one of several nitrogen oxides. NO₂ is an intermediate in the industrial synthesis of nitric acid, millions of tons of which are produced each year. This reddish-brown toxicgas has a characteristic sharp, biting odor and is a prominent air pollutant. Nitrogen dioxide is a paramagnetic bent molecule with C_2vpoint group symmetry.