The key here is that the N2 has a rather weak bond to the O. Therefore it doesn't take much energy to liberate the O, and the single O is highly motivated to find something else to bond with. The N2 by-product is largely inert and just goes out the pipe.Are you sure? I thought the whole point of Nitrous Oxide was that it released a large amount of oxygen in the combustion chamber. If it is N2O then it only has a slightly higher oxygen content that normal air.