I found out that density describes the space inside of something. I also found out that gases do not keep their shape or always take up the same amount of space. They spread out and change their shape and volume to fill up whatever container they are in. By Dominic.
I found out that if you cool a gas, it can turn into a liquid. By Thomas.
I found out that solids keep their shape and dissolving is a reversible change. By Areeba