How is nitrous oxide formed?

Answer 1

Nitrous Oxide is also the gas that they use at the hospital for surgery to make you fall asleep. And the way that they make it is to lightly heat up ammonium nitrate which will turn to nitrous oxide and water vapor.

Answer 2

In combustion.

Actually the answer above is not entirely true. During the combustion process the quantity of NO2 formed is not that significant. NO concentration, however, is much significant. At the high temperatures of combustion O2 and N2 dissociate and form the NO radical and, it is true, a little bit of NO2 (insignificant compared to NO nevertheless). Most of the NO2 is formed in atmosphere after the exhaust plume containing the NO radical cools down and the oxidation with O2 takes place thus obtaining NO2 due to the reaction between NO + O2. The process is very slow but atmosphere has time to wait unfortunately...

To understand how this works you need to look into a chemical kinetics mechanism .

Hope this helps!