12. If the particles of a liquid are always moving, why don't they all come apart from each other and become a gas?

The answer is true for your question.

Aphysical change is one that you can put in and remove like a ham sandwich. the stuff you put in there can be changem its not permanet. a chemical change is on that can't be change thats permanet. like when you make a cake and bake it. you can't get those ingredients back.