Ammonia oxidation in a microreactor
How is nitric oxide used?
Nobody uses nitric oxide 'as is.' It's made solely to be used as a reactant in other chemical reactions. The main use of nitric oxide is to make fertilizer, but that's another story for another time. The main thing to remember is that nitric oxide is made by oxidizing ammonia!
BUT ...
If you're really interested, check out the junior chemical engineer's version of this page.
If you're sort of lost, here's how to get all the way back to the beginning of the high school version