When I think of states of matter I think of Solid, Liquid, and Gas. But there is a 4th state of matter that is actually more common than those 3: Plasma.
Plasma is like a gas in that the atoms are bouncing around and it has no distinct volume or shape. But in a plasma some of the electrons are separated from the atoms, so you get a bunch of positively charged ions and loose electrons. Because of the charges involved, plasma will respond strongly to magnetic fields.
Plasma can be created by taking a gas and heating it, subjecting it to microwaves, or running an electric current through it.
Why is plasma more common than solids, liquids, and gasses?
Well where in the universe would you find a lot of gas that is subject to extreme heat? Hint: plasma also gives off light.
How to make plasma:
Microwave a grape!
Cut a grape in half along its equator. Leave just a little bit of skin connecting the two halves.
Use a paper towel and squeeze some of the liquid out.
Place it on a plate (not paper – it is going to get hot), and cover it with a glass (not plastic – it is going to get hot).
Microwave for no more than 15 seconds. If it does not work in that amount of time, you need to start over.
Be careful when you remove the glass and plate, they will be hot.
Thanks to Veritasium for showing me how to make plasma. Here is a link to that video http://www.youtube.com/watch?v=RwTjsRt0Fzo