Making explosive gas is a basic skill, and doing it can teach you a lot about chemistry. What you use that gas for is up to you. But please be careful.
Aluminum is a metal we take too much for granted. We can't be blamed for that, because aluminum tames itself for us. Whenever it's exposed to oxygen - which you may have noticed flitting around our atmosphere - the outermost layer of aluminum atoms get together with oxygen atoms and settle down into a relatively nonreactive substance.
This isn't a marriage so much as a mugging. If the oxygen weren't lying around, easily available for the taking, aluminum would grab it away from elements, including water molecules. Aluminum is powerful enough to rip apart water molecules, but usually doesn't get a chance, because it's sealed in a casing of its own oxide. There is a way to keep it from sealing itself away from the world. Last week we showed you how you could turn aluminum objects, like soda cans, into paper-fragile substances that you could rip apart with your bare hands. All you had to do was add a little gallium.
The gallium itself will diffuse through the aluminum, making an alloy. A little gallium will make a soda can easily crumple-able. When a mixture of a substance is around twenty percent gallium, aluminum loses its aloof nature. Instead of a protective oxide layer, it is ready to react with anything around it. It is ready, and raring, to mug some water of its oxygen. The hydrogen, abandoned by its oxygen, comes hissing out of the mixture, mad, bad and dangerous to know.
Some people are using this particular mix to make the world a better place. The hydrogen can be used to power engines. The gallium can be recovered by putting lye on the aluminum and gallium mixture (which also releases hydrogen). The aluminum oxide can then be recycled. The world can be a better place.
Alternately, some people can use this trick to blow up parts of the world. Hydrogen is an impractical explosive to do any real damage with - we've realized it can be a bit reactive since we saw what happened to the Hindenburg. But harvesting just a bit, perhaps after you have made a soda can easily tearable, can yield some very fun little bangs. Naturally, before you do any of this, make sure you're in an open area, hair tied back, and nothing flammable close by. Drop the gallium and aluminum in a jar of water, cover the top of the jar, but leave a little hole to put tubing through. (Don't just seal the jar, as the build up of gas will cause it to explode.) As the hydrogen emerges from the mixture, it will go through the tubing to collect in whatever you have on the other end of the tube. I suggest the ever-popular balloon. But if you want to put a little more effort into it, you can use the hydrogen and some kitchen savvy to make an exploding egg.
So the world a better place? Or the world in a few more pieces than it was before? You decide.
Top Image: Marcos Andre