So I’m a huge fan of the manga/anime series 鋼の錬金術師, or in English, Fullmetal Alchemist. I was talking with a friend recently, who said that he couldn’t take it seriously because the alchemy in the show was in no way alchemy. And he was right! The alchemy is more like “magical chemistry”, where you can rearrange all atomic/molecular bonds with the ~power of your mind~ (or as it was retconned later, the earth’s geothermic properties. Personally I preferred power of the mind, but YMMV.)
Anyway, I have a much longer blog post on this to come, but if you look closely at the series, a lot of the alchemy works neither as alchemy or chemistry. This doesn’t put me off in any way, of course, because it’s a fantasy series, and it’s fairly consistent within the show, which is the most important part.
But none of that has ever stopped intrepid nerds such as myself, who are bound and determined to make it all make sense somehow. So! I wanted to talk about my favorite character, Colonel Roy Mustang, and his “flame alchemy”, and how utterly WTF it kind of is.
Roy Mustang has the ability to make things go boom. He wears gloves that, when rubbed, make sparks (like flint and tinder). It is stated canonically that what he does is light a spark after he “adjusts the concentration of oxygen in the atmosphere, and boom!”
At this point, every chemist in the audience is saying “what the fuck? it doesn’t work like that!”
Because oxygen does not light on fire by itself.
Let’s back up. Combustion is a reaction of a reductant (fuel), and an oxidant. Oxygen is, as you would guess, often the oxidant. For instance, if I am burning a piece of wood, the hydrocarbons in the wood fuel are my reductant. Of course, fuel needs oxygen to burn. But very pure oxygen will in fact not burn, because it has no fuel to burn! It’s always something else in the area that burns—a match, a cigarette, clothing, furniture.
So let’s back up. Roy Mustang snaps his fingers and flames go whoooooosh in the air.
But what’s it burning? Nothing! There is no fuel for these flames! Chemistry does not work this way! (Okay, sometimes he is lighting
homunculi people on fire, but just as often, we see flames literally in thin air.)
So, how can flame alchemy possibly be working?
Worry not, for I have a solution to the problem. You know what else air has lots of? Nitrogen! The earth’s atmosphere is 70% diatomic nitrogen (N2). This is great because N2 is extremely stable, and doesn’t burn or react with anything else.
However, this means that any reaction that gives out N2 as a product will be extremely exothermic (that’s chemist for “goes boom if you look at it the wrong way”). That’s why you hear so much about nitrogen-based explosives. Most of these are azo/azide/nitro based, but the problem with those is they all contain carbon as well. We can’t have that; there simply isn’t enough carbon in the atmosphere (which is a good thing, global warming and all that).
Query, then: what can you do with nothing but nitrogen? Answer: you can chain together a ton of azides. This gives you extremely unstable, explosive compounds. Roy Mustang, who can split water into hydrogen and oxygen with his mind (extremely hard to do in real life, and the focus of much research), could certainly rearrange nitrogen atoms into incredibly unstable configurations.
But don’t just take my word for it — intrepid chemists have made it in real life. Taken from “Things I Won’t Work With” on a popular chemist’s blog:
As you can see, this is made entirely of nitrogen, so it can be made from nothing but the Earth’s atmosphere. And as to where it will light on fire? Here, from the post:
"The compound exploded in solution, it exploded on any attempts to touch or move the solid, and (most interestingly) it exploded when they were trying to get an infrared spectrum of it. The papers mention several detonations inside the Raman spectrometer as soon as the laser source was turned on, which must have helped the time pass more quickly.”
In conclusion: what up, Edward Elric? Were you wanting to show up Colonel Mustang? I’ve just solved Flame Alchemy for you — in return, please just give me a running head start to get the hell outta Central before the showdown.
(P.S. I haven’t even gone into the extremely complicated fluid dynamics and atmospheric chemistry that Roy would have needed to master flame alchemy. The man would have to be a math genius. I’m cool with that.)