Section 1
Pure vs. Mixed
Key Idea
We know that a pure substance is made of only one kind of molecule. But most things in the world are not pure; they are combinations of different things.
When two or more different substances are combined, they form a mixture. Think of a bag of trail mix with nuts and raisins. The nuts and raisins are in the same bag, but they are still separate items. In a chemical mixture, different types of molecules share the same space, but they stay separate and do not turn into something new.