Quick, what are the states of matter?
If you said solid, liquid and gas you are almost right. Almost? It turns out that many scientists now agree there is a fourth state of matter called plasma, and very possibly others. It is distinct from the other states of matter in its properties and it is extremely common. In fact it is the most abundant state of matter in the universe by far.
If it is so common, then why hasn’t everyone heard of it? Or if you have heard of it, why aren’t you really clear what it is?
One problem may be the term plasma. Plasma is a word also used for the fluid in blood that carries the cells and other materials from place to place. Same word, two very different meanings, but that happens all the time in the English language.
The state of matter plasma is a gas that has been energized so much some of its electrons have come flying off. It can also be called ionized gas, but that is confusing because it sounds like it is just a special kind of gas. Scientists have realized that plasma behaves differently from gas, and is a separate state.
To help you develop a better understanding, let’s look at some examples of plasma.
A flame is a simple form of plasma, where only a few of the gas molecules have lost their electrons and become ionized. Lightning is a much more intense form of plasma. The sun and stars are plasma.
You can even have plasma in your home, if you have any neon signs or lamps. You can also buy plasma balls. Inside the glass ball, electric fields pass through a gas that has been charged to make it plasma. Here is a YouTube video that shows one.
If your children are not very familiar with the concept of an atom, it might be a great time to review. One of my favorite demonstrations of atoms uses a pile of oranges and some tennis balls. The oranges are the protons and neutrons and they sit in the center of the atom. You can put a P or N on the oranges, too. The tennis balls are rather wacky and can bounce around all over the place. They are the electrons. If you have gone over the periodic chart, then find some actual elements to create using the atomic mass and atomic number. Choose a simple gas like helium, which has 2 protons, 2 electrons and 2 neutrons. Relate your atom to the gas found in balloons that makes them float.
Once you have created a few atoms, now you can strip away the tennis balls, leaving the oranges. Now you have created plasma, a gas that has lost some of its electrons and has become charged or ionized. Note: not all the electrons need to be lost, and not all the atoms have to lose electrons. Only a few lost will be enough.
The Coalition for Plasma Science has educational materials and links to other websites.
I also found a fun game to help understand plasma by sorting items into the different states of matter at the Space Weather Center.
Here are a few plasma balls you can buy for your own experimentation in various sizes and prices. Just remember they are made of glass, and be careful with plasma balls around young children.