well theres a difference between NO2 Nitrous Oxide and N2 nitrogen, N2 is unreactive wheres NO2 (laughing gas i think) i used a propellant in race cars! No2 is normally reffered to as Nitro, now i am pretty sure of this... but not 100%! If i could be a****d i'd go and check my A lvl chemistry book but i can't! So if im wrong plz say!