| @Rackie: `Nitrogen oxide' is too vague. Nitrogen has three common oxides: N2O (nitrous oxide, dinitrogen monoxide, `laughing gas'), NO (nitrous oxide, nitrogen monoxide) and NO2 (nitrogen dioxide). There are also the more exotic N2O3, N2O4 and N2O5, which are explosive — dinitrogen tetroxide is used as an oxidiser in some rocket fuels. |