Don Pettit, on the international space station, swiped everyone's candy corn - for science! In this video, with candy corn, water, and oil, he shows how soap molecules clean people's clothes. Then he pigs out on the candy corn.
Soap molecules are a collision of two kinds of molecules. One is polar, meaning it has a slightly positively-charged side and a slightly negatively-charged side. It isn't an overall charged molecule. It just has its atoms arranged so that the electrons are hugged a little tighter to one atom than another. Water also has slightly charged sides, since the hydrogen molecules have a looser grip on their electrons than the oxygen molecule. The electrons hug close to the oxygen, giving it a negative charge. Polar molecules interact well with each other.
Not all molecules are polar, though. Nonpolar molecules have a very even distribution of charge, and don't interact with polar molecules at all. Fats and grease are nonpolar, which is why they don't lift out when washed in water. Soap works because it links its polar molecule to its nonpolar molecule. This lets it interact with both water and the kinds of substances that resist being lifted away by water.
Don Pettit demonstrated this by dunking the pointy side of the candy corn in water, and the blunt side of the molecule in oil. This gave it a polar and nonpolar side, like soap molecules. He then made a floating blob of water. When he added candy corn to the water, its polar side automatically oriented itself toward the water, and its nonpolar side oriented itself away from the water. Once enough corn was around the water, it formed a stable blob of nuggets that could be manipulated.
Soap works much like this, except instead of the polar, or hydrophilic, ends being towards the center blob of water, the nonpolar, or hydrophobic, ends of the molecule would be oriented around a central blob of oil. Eventually the soap would completely surround the oil, latching on to it. Meanwhile, the polar ends of the soap molecules would be grabbing hold of water washing around the blob, and the entire structure would be lifted away.
Something strange happened in this experiment, though. Instead of just being manageable, the whole blob went solid, and became a chunk of candy that could be squeezed without deforming. This could have lead to a whole new Corn in Space theory of physics, but unfortunately Pettit had already eaten all the candy corn on the station.
Top Image: Evan-Amos