If you picture this with something like lots of small magnets, it's evident enough that you get a solid phase, i. Now, if you increase temperature, that's like thoroughly vibrating your magnet sculpture. Because these bonds aren't infinitely strong, some of them will release every once in a while, allowing the whole to deform without actually falling apart.
This is something like a liquid state. Small and sturdy molecules or single atoms aren't so bothered by high temperatures though. They also don't have so strong forces between molecules. So, if you shake strongly enough, they simply start fizzing all around independently. That's a gas then. Now, the question why a particular material is in some particular state at some given temperature and pressure isn't easy to answer.
You need statistical physics to predict the behaviour. The crucial quantities are energy and entropy. Basically, the random thermal motion tends to cause disorder which is quantified by rising entropy. At any given temperature there's a corresponding amount of energy available to overcome the attractive force, and within that energy budget the system approaches the state with the highest entropy.
A solid has little entropy, but if there's not much energy available this is the only feasible state. A liquid has higher entropy but requires some energy to temporarily unstick the molecules. A gas requires enough energy to keep the particles apart all the time, but is completely disordered and therefore has a lot of entropy.
But how much energy and entropy a given state has exactly varies a lot between materials, therefore you can't simply say solid-liquid-gas. Physics is about observing and measuring nature and then finding mathematical models that fit the measurements and predict new behaviors under different conditions.
Because we have observed these four states of matter. All these processes are described perfectly using quantum electrodynamics and thermodynamics as also described in the other answers.
That is the mathematical map of the nature we found ourselves in. That's the way the cookie crumbles, That's the way the ball rolls, etc If there were only one phase, a different set of theories would describe them, not the ones that describe successfully our present world. Basically the existence of different states of matter has to do with Inter-molecular forces , Temperature of its surroundings and itself and the Density of the substance.
This image below shows you how the transition between each states occur called Phase transitions. But there are other exotic states of matter out there, like Plasma and Bose—Einstein condensate. This is one of those funny questions where the cart gets put before the horse. Matter doesn't "exist" in any state. It simply does what it does, in the way it does it. Humans, wishing to understand how different types of matter behave chose to create a system of three states.
This choice is the key: the reason "matter exists in 3 states" is because we chose to model it that way. It would be trivial to declare "matter exists in 5 state" or "matter exists in 2 states. For example, we find that the way a solid object, like a rock, behaves is fundamentally different from a liquid, like a stream of water, because for the kinds of things we worry about, its a useful distinction.
Getting hit in the face with a rock is typically a very different event than getting sprayed with water. We do have rationales for why these states occur, based on the concept of intermolecular forces. In a solid, molecules have very little freedom of movement because the intermolecular forces trap them. Solid things have rigid behaviors. In a liquid, molecules have enough freedom of movement to go anywhere in a volume, but the intermolecular forces still have a large effect on how they behave.
This mobility leads to traits we found important enough to categorize, such as fluidity. In gases, molecules have so much freedom of movement that the intermolecular forces become more of a side note when it comes to predicting their behaviors.
What we have found is that, in many cases, the lines between these behaviors are rather sharp. The transition between solid to liquid or liquid to gas tends to happen very close to a particular temperature. Noe that I say close: the process of boiling or freezing is a statistical one, not an exact one. For most of what we do, these two divisions, between solid and liquid and between liquid and gas, are effective enough at helping us understand the universe that we consider them "fundamental.
High energy physicists consider the case where the thermal energy of a gas gets so high that it starts to strip its own electrons off, becoming nothing but a bunch of ions. This material behaves differently enough from gas that they declared it a new "fundamental" type for one thing, it's affected by magnetic fields!
It has been found, that for many materials, its properties are well described by these categories, so we keep them! On the other extreme, there's many cases where "solid" is not actually enough to capture the behaviors we care about.
In these cases, we adapt. My favorite example is chocolate, because chocolate is a strange beast of a material. You can melt it solid to liquid , and the crystals of chocolate fat dissapear as you'd expect. However, some crystal structures are more robust than others, requiring higher temperatures. Likewise, the crystals form at different temperatures as you cool it. This leads to some remarkable chemistry. As it turns out, there are 6 "polymorphs" of the chocolate fat crystal, each with their own properties.
Of them, only Form V is good for chocolateering. It's the crystal which has the charactaristic snappy crunchy feel we want from chocoloate. Thus, when one tempers chocolate, one first raises the temperature to melt all crystals. Then one reduces the temperature to cool it down and form crystals the more the merrier. After this, you raise the temperature to between Then, one pours the chocolate and let it cool, leaving only Form V crsytal structures.
Note that all that I talked about dealt with solids, crystal growth. Through the entire process, the average layman would call that material 'liquid,' but I'm constantly freezing and melting things within that liquid state. The simple concept of "liquid" just isn't enough. To try to answer what I think is your underlying question, rather than the specific wording you use The electro-magnetic forces are only so strong.
Let's say you have a box half-full of some molecule. Electro-magnetism keeps the individual atoms together keeping the electrons bound to the nuclei and it keeps the molecules themselves together which, simplified, is actually the same as the previous case - the key is keeping the electrons bound to the nuclei again; it's just that the electrons are shared between two nuclei at a time to an extent.
Finally, the molecules in the body can be held together by the same electro-magnetic forces to form solids or liquids. When dealing with states of matter, we usually most frequently talk about heat and pressure.
To simplify, I'm going to merge the two together - it's not very useful in practice, but let's just see where we get. We've already said that the individual molecules let's pretend that all matter is made out of molecules for now have some kind of attraction between themselves.
These "bonds" have a certain potential energy - basically, a measure of how much energy you have to add to break the "bond". For example, a molecule of nitrogen holds together much more strongly than a molecule of oxygen, so you need more energy to break down nitrogen than you need to break down oxygen.
One way to look at heat is as the average kinetic energy of the individual parts that make up matter, which is useful when thinking about the states of matter. The higher the heat, the higher the chance that any given "collision" will have enough energy to break that inter-molecular "bond" that determines the state. All in all, it's a balance between all the forces acting on the constituents of matter. Water is the only substance present in nature in the three classical states, and it is also the substance in which, at the beginning of , a new form or state of arrangement was discovered: superionic ice.
That brutal pressure forces the ice to adopt a very compact packing , but, at the same time, the high temperature dissolves the bonds of the water molecule. The result is that in superionic ice two phases coexist: one liquid and one solid. Oxygen atoms adopt a crystalline structure, through which hydrogen nuclei flow. It is believed that superionic ice could exist in large quantities in gaseous and icy giant planets such as Uranus or Neptune, within which the appropriate conditions for its formation are found.
If it were confirmed that other substances subject to similar conditions also adopt this arrangement, we would be in the presence of a new state of matter. Miguel Barral.
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Astronomy Astrophysics Discovery Research. Ventana al Conocimiento Knowledge Window. Estimated reading time Time 4 to read. Plasma The plasma state is the one in which the gases contained inside neon lights, fluorescent tubes and, of course, plasma screen TVs exist. A plasma globe operating in a darkened room. Credit: Chocolateoak Plasma is an ionized gas at a high temperature.
It does this by either using or releasing energy, and it is usually associated with changes in temperature and pressure. A simple example is water. If you have a block of ice, you have solid water.
Add heat a form of energy and the ice melts into liquid water that you could drink it has reached its melting point. Continue to apply heat, and the water will evaporate and turn into steam, which is water in a gaseous state it has reached boiling point. This works backwards, too. Gas can cool down by losing energy and condense back into liquid water and cool down further into a solid. There is even a process called sublimation where a solid can turn straight into a gas when heat is applied.
Slumpy solids or lumpy liquids explores a range of common household substances to determine if they have the properties of a solid, a liquid or both.
Exploring states of matter uses concept maps to explore current ideas about states of matter. Use this unit plan, aimed at middle primary, to experiment with various liquids, including non-Newtonian fluids, to see how their viscosity is changed by stress or force. Add to collection. Activity ideas Slumpy solids or lumpy liquids explores a range of common household substances to determine if they have the properties of a solid, a liquid or both.
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