How Do You Remove Salt from Water?

I've been asked "How do you remove salt from water?" enough times that I suspect finding the answer to the question is a common science assignment. So... how do you do it?

You can boil or evaporate the water and the salt will be left behind as a solid. If you want to collect the water, you can use distillation. One way to do this at home would be to boil the saltwater in a pot with a lid. Offset the lid slightly so that the water that condenses on the inside of the lid will run down the side to be collected in a separate container. Congratulations! You've just made distilled water. When all of the water has boiled off, the salt will remain in the pot. Evaporation works the same way, just at a slower rate.

To evaporate water to obtain salt, place the salt water in a wide, shallow dish. This shape offers maximum exposed surface area, which aids evaporation. You can speed up the process by placing the dish in a warm, sunny window or by blowing a fan over it. If you place it outdoors, evaporation is quick on a warm, sunny, breezy day. It will be slower on a cloudy, cold, or humid day.

Crystallizing salt from salt water doesn't leave behind pure water, although it does remove a lot of the salt. The remaining liquid will be a less-than-saturated solution.