Dissolving and Filtering

Separating substances from each other can be a difficult problem. However there are certain 'rules' that actually help you to make sense of it, like if you've mixed two things in water, one which dissolves and the other doesn't, then you can always get them apart by filtering (like a very fine sieve). Similarly, if you want to get the dissolved substance back out of the water, you simply evaporate the water away.

Let's practise some of these ideas and see how you get on......