The scientific way to make alcohol disappear

No, not that way. That'll come later. For now, you can get some (purified) ethanol and some water, and do a quick experiment that involves one of those thing disappearing into the other. All you need is some water, and some ethanol, a cup measure and a glass or two to mix them in.

First get a cup of water, and another cup, and add them together. You'll get two cups of water. I know. Stunning.Do the same thing with the ethanol, and you'll get the same result.

Then take a cup of ethanol and a cup of water. You'll end up with a bit less than two cups. Not a lot, a few teaspoons are missing — but where did that volume of liquid disappear to?

Get up close to molecules and they don't resemble liquids (or gases) so much as they resemble a bunch of uniformly-shaped gravel. Water is big and clunky, and takes up a relatively large amount of room — at least compared to ethanol. The smaller ethanol molecules fit around the water molecules in a glass the way packing peanuts fit around objects in a box. Add together two volumes of liquid and you get a volume less than the sum of its parts. Scientists have to take this into account when they actually start mixing fluids together —measuring two parts doesn't necessarily mean knowing the measure of the whole.

As a note, most of the ethanol you have on hand isn't pure. Put together 50 milliliters of ethanol and 50 milliliters of water and you will lose four milliliters of volume. Wine, beer, vodka, and other home sources of ethanol already have a lot of water in them, so you might have to make them disappear the old-fashioned way.

[Via Chemistry]