Salting out

Okay kiddo, have you ever tried to make chalk dissolve in water but it just wouldn't mix well? That's kind of what salting out is like!

So, imagine you have some water and you want to mix in some salt. At first, the salt dissolves really well and you can't even see it anymore. But if you keep adding more and more salt, eventually you'll notice that the water starts to get cloudy and the salt doesn't seem to be dissolving anymore.

This is because the water can only hold so much salt before it becomes saturated. When there is too much salt, it starts to form little chunks or crystals that can't dissolve in the water.

Now, let's imagine that you have a mixture of different substances in water, like oil and water or different kinds of chemicals. Some of these substances might dissolve well in water, but others might not.

If you add salt to this mixture and mix it up really well, you can make some of the substances "salt out" of the solution. This means that they form little chunks or crystals and separate from the other substances in the mixture. It's like when you put pepper on top of water with oil, and the black spots start to clump together and stick to the oil.

Scientists use salting out in lots of different ways, like to separate DNA from cells or to purify proteins for medicine. It's a clever way to "trick" certain substances into coming out of a mixture, just by adding salt!