When I was in grade school, I was taught that there were three phases of matter – solid, liquid and gas. It turns out that there are substantially more types of matter in the universe.

The three states of matter that I learned about in school are the more common phases of matter, those we see daily. Then, there are the more exotic phases of matter, including Bose-Einstein condensates, superfluids and liquid crystals.

However, the phase of matter most commonly observed in the universe is probably plasma. One example of a plasma that you are no doubt familiar with is the material inside neon lights. The material inside the tube is rarefied neon in a plasma state. Where we see plasma the most, though, is in the fire in our fireplaces, on our stovetops or at lighting events like WaterFire. What makes plasma so special?

The best way to understand states of matter is to think of how energetic the atoms of a material are. Like with most things in life, the more energy something has, the more it tends to move around. If we could look at the atoms in frozen water, we would seem them sitting very still. As the ice melts and turns to water, the atoms begin to move around a little more, and if we give the water more energy, the atoms start to move away from each other and turn to an even more energetic form of matter – a gas (or more commonly, steam). If we increased the energy of the water further, we would eventually find ourselves with a plasma form of hydrogen and oxygen.  Our sun is primarily made of hydrogen in a plasma state.

The key difference between a plasma and a really hot gas is that in a plasma, a large portion of the atoms have become ionized. Ionized materials are affected by electric fields. That is, if you put a candle between two metal plates with different electrical charges, the flame would change shape and conform to the flow of electricity between the plates. Now, this all seems a bit technical and abstract, so what is really the difference between hot things like a red-hot stove and a flame? After all, we cook with both. So why do so many chefs prefer that open flame? Well, as it turns out, plasma is just hotter.

To become a plasma, a material must have much more energy than one might expect. For example, the flame in your fireplace or in your grill is probably around 3,590 degrees Fahrenheit. Compare this to the melting point of iron, which is about 2,912 degrees Fahrenheit. That means to get the same temperatures from your electric stove, you would need to heat the metal heating elements until they melted. Not so easy to set a pot on! These higher temperatures are why we rely on plasmas to heat our food and homes – the material is just hotter.

So when you are sitting around a campfire some night this summer, you can wow your friends and family by telling them the flame that everyone is watching is a fourth fundamental state of matter – plasma.

By R.J. Linton