Why is Plasma the Fourth State of Matter, and Why Wasn’t it Taught Alongside Solids, Liquids, and Gases? #PlasmaState #MatterStates #ScienceEducation
Have you ever wondered why teachers often skip over the fourth state of matter, plasma, when teaching about solids, liquids, and gases? Let’s dive into why this fascinating state is sometimes overlooked in early science education.
The Basics: Solids, Liquids, Gases
When we first learn about matter in school, we’re introduced to the three classical states: solid, liquid, and gas. These are the most common states we encounter in everyday life, so it makes sense that they are emphasized in early education.
Introducing Plasma: The Fourth State
Plasma, on the other hand, is less commonly encountered in our daily experiences. It’s a state of matter where atoms have been ionized and stripped of their electrons, creating a highly charged, electrically conductive substance. Plasma is found in lightning, stars, and even fluorescent light bulbs.
Why the Delay in Teaching Plasma?
So, why weren’t we taught about plasma along with solids, liquids, and gases? One reason is that plasma is often considered more complex and less intuitive than the three classical states. Its properties and behaviors can be challenging to grasp without a solid foundation in basic chemistry and physics.
Another factor to consider is that education curricula are designed to build upon foundational concepts, gradually introducing more advanced topics as students progress through the grades. Plasma is typically covered in more detail in higher-level science courses, where students have a better grasp of the underlying principles.
In Conclusion
While plasma may not be taught alongside solids, liquids, and gases in elementary school, it’s still a crucial state of matter to understand. By delving deeper into the world of plasma, we gain a greater appreciation of the diverse forms matter can take and the complex interactions that govern our universe. So, next time you see a lightning bolt or a neon sign, remember that there’s more to matter than meets the eye!
For the same reasons you don’t learn calculus in elementary school
Solid liquid gas are very common in basic science theory/education and have a broad application to many career paths…..plasma is abundant in the universe but not a common natural state of matter on earth
Understanding plasma requires more fundamental building blocks of science like electrons
Because then we would be having this same conversation about the 5th state of matter, the Bose-Einstien condensate.
Showing the 3 phases of matter with water is so much easier for a child to grasp. Water can’t really exist as a plasma, rather the hydrogen and oxygen would be the plasma. Breaking down of molecules is a bit advanced for a child.
The first three states are things that people encounter every day. The fourth is something most people will never encounter in their lives, and even physicists researching it specifically do so with a lot of protective equipment (or telescopes) between it and them. Telling second graders about it would just make the other three states more confusing.
One could argue there are more than 4 actually. But understanding them would require a high level physics so the easy ones are taught instead.
Google superfluidity videos if you are interested in something almost fictional.
There are more than 4 states of matter. There are more than 5 states of matter. In fact, it turns out to get difficult at some point to decide if an observation is a new state of matter or not. But most people agree there are 3 states of matter that every person interacts with every day.
Somehow I haven’t seen this answer yet: the “basic” 3 states of matter are the only ones where the atoms are intact. Plasma, exotic condensates, etc all involve subatomic particles. But if you’ve got electrons bound to a nucleus, you’re talking about either a solid, liquid, or gas.
Same reason why you’re also taught Newtonian mechanics, and not quantum mechanics and General Relativity. Because unless you’re going into a field where you need those, it’s just too much information.
Case in point, there’s many more states of matter than those 4. You don’t even need to go to edge cases like plasma or weird quantum studf to get there, because normal everyday matter can also exist as in-between states in normal circumstances. You get stuff like supercritical fluids, where gas and liquid are no longer two different things. In mixtures and alloys, you get solidus and liquidus, where the mixture is in the process of freezing but there’s not yet a clear distinction between liquid and solid, but a combination of the two. There’s more.
Hell, at least the three states of matter are factually correct, they exist as described, there’s just more to know out there. Most of physics (again, like Newtonian dynamics) you learn at school is technically incorrect, when you get down to actual details. It’s just approximately close enough that >90% of humanity will never be in the position to tell the difference, so it’s fine.
Because plasma isn’t really a state of matter, at least not in the same way. Let’s take water as an example. As a liquid, water is H2O molecules bouncing around next to each other. They have enough energy not to get stuck (intra-molecular hydrogen bonds) but not enough to keep them flying all over their container.
When they freeze, they have so little bounce energy to then that the weak attraction between hydrogen atoms on separate molecules is enough to pull them into a crystal shape. But they don’t become one giant molecule. They still have all the chemical properties of H2O atoms.
When they boil, they bounce around so hard that they are fairly evenly distributed throughout their container (bottle, pot, the air above your stove in the kitchen). But they still have all the chemical properties of H2O atoms.
They all act the same chemically, and **crucially** we can go back and forth between these states easily. Plasma is different.
When you keep heating matter beyond where it vaporizers, it starts bouncing hard enough that the molecules basically explode. So keeping to our water example, each H2O molecule separates into 18 free electrons, 2 free protons, and 1 big conglomeration of 8 protons and 8 neutrons. A water plasma **NO LONGER** has the chemical properties of water. Also, when you let it cool off, it won’t turn back into water nicely. You’ll get hydrogen molecules (H2), oxygen molecules (O2), likely some ozone (O3), and random bits of acid (H+) and base (OH-).
So, to TL;DR, plasma is made up of all the same subatomic particles as the matter it came from, but is not the same substance, and doesn’t readily transition back and forth. So while it’s sometimes called the 4th state of matter, it’s really a different category entirely from the solid/liquid/gas states.
They also didn’t teach you about Bose Einstein condensate, quark gluon plasma, supercritical fluids, time crystals, etc. there are way more than 4 states of matter and tbh, a state of matter is not really a thing. You don’t, however, need to worry about anything but solid, liquid, and gas in your every day life because those are the only three that regularly exist on earth. There are others that do exist here you just never encounter them (think deep sea vents or the mantle, or alternatively at the collision point of cosmic rays, you can’t observe these normally).
Plasma is *exceptionally* Rare, iirc. Besides stars, the only place it naturally exists is at the impacts of lightning strikes.
It was explained to me that plasma is not normally encountered in nature except in lightning bolts, so it is difficult for most elementary school kids to comprehend. Similar to why advanced math is not taught in elementary school.
Last Airbender basically had it covered:
Water (liquid), Earth (solid), Fire (plasma), Air (gas)
You typically do not encounter plasma in most situations on earth, so it won’t be taught until later. Furthermore, there are actually many more states, such as Bose-Einstein condensate.
https://en.m.wikipedia.org/wiki/List_of_states_of_matter
People are postulating good reasons, but some of it’s also age and curriculum. Plasma and BEC are (relatively) new states of matter–I didn’t learn them in elementary school in the early 00’s, but my sister (who is about ten years younger) learned all five in first grade–although I think really grasping anything more than the names or that they exist at extremes of temperature (roughly) is more of a “gee whiz” for most people.
Same reason why Newtonian physics is taught in high school instead of modern physics. It’s much easier to explain and gives a base of knowledge. It’s also much easier to see and do in a basic elementary science class.
There’s actually many, many states of matter beyond those 4, and lots of different phases. We interact with solids, liquids, and gases a lot more readily than the other ones in everyday life, so we start with the basics there. Save the Ld, Lo, and Lβ lipid phases until graduate school.
Iirc plasmas ionize the atoms in the plasma field, so while you can have water in solid, liquid, or gas form, it’s becomes a bit more like a hydrogen oxygen plasma, and the reactions become even more complex, so it’s not often even able to be taught in secondary school.
States of matter, as with any other topic, are way too complicated and murky to fully teach to children. In reality, there’s a lot more than four states of mater, and they’re not as clear-cut as you think. Leaving out plasma is just one of the many, many simplifications schools happen to make so the topic can be approachable to someone outside of the field of study (again, as with any topic). If you were to teach all of them, you’d have to dive into Bose-Einstein condensates, supercritical fluids, crystalline and non-crystalline phases, etc. The line has to be drawn somewhere.
In reality, states of matter don’t really “exist”, they’re not a real property of materials, they’re a (very useful) simplification we make to help in categorising them. There’s no single material that falls cleanly into one of the states and not the others. It’s more of a sliding scale than rigid boxes. Every material has a certain level of viscosity, even the strongest of metals, so they’ll behave like a fluid if you push them hard enough. Think going from air, to water, to honey, to play dough, to plastic, to metal. There’s never a clear separation where you can say “this is a liquid, and this isn’t”.
Most people interact with matter in solid, liquid, and gaseous forms daily.
Many people encounter plasma often, but most people don’t get close enough to lightning to need to think about the matter that it is in contact with. Most people who use plasma, such as with cutting or welding torches, don’t need to have a precise understanding of what makes plasma different from running an electric current through gas in order to use it.
Plasma just isn’t a part of our daily life the same way even if we encounter it more often in more situations than a lot of people realize.
And there are other states of matter. In general, you aren’t going to ever have a reason to learn what makes these distinct. For example, I do not understand quantum science. I therefore have no understanding of what Bose-Einstein condensates are. I just know that they’re a thing that exists at extremely low temperatures. My life wouldn’t be any different if I didn’t know about these. Almost everyone whose life is meaningfully different as a result of knowing about them is a physicist.
In my high school science classes, plasma was discussed briefly. We were told it’s a phase you’re unlikely to encounter much on Earth.
99% of the population don’t need to know plasma is a thing. Everyone should know about about solid liquid and gases.
But even then do they realize I could make copper gas if I heated some up enough? But another again not something most people have to know about
In my school they did say “The fourth state is plasma, which is something we aren’t going to cover. It’s hard to describe at this point to you because you need to know more about the other 3 states first”. And yup, later on if you started taking electives for astrology, or physics, they then covered plasma.
It’s really easy to show the 3 states of matter to a child. Showing them plasma (or others) is more difficult.
Because the overwhelming majority of what we interact with is one of the 3 states of matter were taught, and what makes them distinct is understandable with the things we already know. Yes I know the sun is plasma and is a pretty important part of our lives, but our perceptual understanding of it doesn’t really “show” us what plasma is, we kind of broadly understand it as just a hot bit of light
Understanding what distinguishes plasma from gas takes a few more pieces of understanding that’s a bit more complex
Ultimately it’s just useful to be able to point to things we see every day as examples of them, plus that’s all most of us need to understand, so they tend to leave out states of matter that exist in niche extreme circumstances, plasma being among them
This is a pretty interesting question.
We teach kids the 3 states of matter because for all practical purposes, we will only ever come in contact directly with those 3 on a daily basis.
But. The really interesting thing is, there may have been a time when folks were only taught 2 states of matter because gases weren’t known. This blows my mind, honestly. To think that there was a time when we were so ignorant, and yet we’ve come this far!
And if at some period of human civilization we come to a point where we deal with plasma on a daily basis, then we’ll be forced to teach it in schools.
Because that’s all you have experience with as a kid. I have engineering degrees and have had a course in plasma physics, and I still don’t have anything that I would call “experience” with plasma, except maybe watching lightning or shocking myself on the light switch and seeing the little blue spark.
Essentially, the places where plasma can exist sustainably are not places where children can exist sustainably. So we just let the curious ones find out about it later.
Because if little Braxtynn spills a pitcher of water all over the desks, it’s a small mess. If it’s a pitcher of plasma… It’s a bit messier.
Gotta keep it in classroom context! Lol!
Because understanding what a plasma is requires understanding how electrons work in atoms and that’s well beyond intro material.
There’s also supercritical fluid and several other exotic states of matter, so there’s no reason to think plasma is a special state you should be taught.
Because teaching kids is a multi-phased process, if I may make that pun.
You start with broad basic things. That’s a tree. Trees are green. Trees have leaves.
Then add more detail. Trees need water and sunlight to grow. Sometimes leaves fall off in Autumn.
Then more. Trees get energy from sunlight using a process called photosynthesis. Trees make oxygen.
Then kids get a bit older and you start to specialise. The kids who are interested in science start to get the detailed information. The equation for photosynthesis. Cellular respiration. The fact that trees are net producers of oxygen but actually use oxygen too. How the leaves and chlorophyll actually work. How the energy is transported around the tree to where it needs to be, etc.
The person who didn’t do any science subjects in the upper years of high school might be expected to walk away knowing that trees produce oxygen, use photosynthesis, and need water and sunlight to grow. These people would also be expected to know that there are three states of matter. Sure, there are others, but there is no practical need to know about them. Same as there is no practical need to know the chemical equation for photosynthesis.
The people who do the sciency subjects would learn about other states of matter, because it is relevant to the stream of education they have chosen. But their knowledge of art may be limited to knowing the name of half a dozen famous paintings and being able to draw stick figures. Or their knowledge of English might be limited to having read a few books and knowing basic writing skills.
There’s a great bit in an Angela Collier video where she touches on this.