That all sounds pretty correct to me, though to be honest I never use Wikipedia as a reference source. I could head on over there and alter one or more of those chemical equations and it probably wouldn't be picked up for a couple of days.

When it's not a controversial subject, you can often rely upon Wikipedia, but even then, there are people who spend their free time adding inaccuracies to random Wikipedia articles (I know one of them. He does it in the name of discordianism).

On the specific subject of manufacturing nitrous oxide from fertiliser (ammonia nitrate), I knew a chemistry postgrad who made some cash on the side by selling nitrous to heads. This guy was one of the best chemists I'd ever met, and even he damn near killed himself one evening.

Heat the stuff too quickly and it'll explode rather forcefully. Heat it too slowly (his mistake that night) and you start to get all manner of ammonia-derived vapours being emitted. Inhale them and you're in very serious trouble!