States of matter

0:00- [Narrator] When you look around, you find three states of matter. We have the solids that you find in the rocks and the trees. Then you have the liquids like the lemonade that you're carrying or the water in the lake. And, finally, we have the gases, for example, the oxygen that you breathe in and the carbon dioxide you give out.

0:16You also have humidity, which is basically water vapors, and you also have nitrogen in the air. All of these are examples of gases. So the goal of this video is to try and understand these three different phases in more detail. So let's begin. Okay, let's start with the first one, the solids.

0:31If you could zoom in, what would we see? Well, remember that all matter around us is made of tiny particles like atoms and molecules. So here, if you could zoom in, you would actually see these atoms and molecules pretty much locked in place. They're wiggling around, but, if you see, look, they're pretty much locked.

0:48That's why they have a fixed volume and they have a fixed shape. I mean, yeah, you can surely pick up a solid and move it from one phase to another, or you can break it into pieces, but as long as you don't do that, they will have a particular shape and a particular volume.

1:04Another interesting thing about them is that if you try to squish it, like I'm trying to squish the lock, which is a solid over here, you can't. (laughs) They're insquishable. In other words, we say solids are incompressible. You cannot compress them. So the particles inside solids are wiggling.

1:19They do have kinetic energy, but they are pretty much locked in place. As a result, they have a fixed shape and volume and are incompressible. Let's look at liquids next. Let's see what we get if you zoom into your lemonade, or maybe let's zoom into the water from the lake.

1:32That's, I think, much simpler. So if you could zoom in, we would see water molecules, but what are they doing? Look, not only are they wiggling, but they're also moving around. You can see that they are close together, but they're not as tightly packed as they would be in solids.

1:47That's why they can easily move, and that's why liquids flow. Therefore, liquids do have a fixed volume, but they do not have a fixed shape because they can easily flow. This is why they take the shape of the container. For example, over here, look, the liquid is taking the shape of this container, but now, if I pour it over here, the volume stays the same, but now it takes the shape of this container.

2:09It does not have a fixed shape because it can flow. But what about its compressibility? Can you squish it? Well, let's see. Fill a bottle completely with water, and try to squish it. You will see it's very hard to do that. I mean, over here, I can kind of do it because there are some air pockets over here, so it squishes a little bit, but if it was completely filled with water, no air pockets, it'd be very hard to do that.

2:29That means it is incompressible. Liquids are also incompressible. So, just like before, the particles of liquid do have kinetic energy, but, this time, they're not just jiggling, but they're also moving around. Alright, this brings us to gases. If you could look inside gases, what we'll find is that this time particles are completely free from each other, and they're completely free to move as they want.

2:51Sure, they do come close to each other and occasionally bump into each other, but they're not closely held together at all. As a result, gases neither have a fixed volume, nor do they have a fixed shape. They will take both the volume and the shape of the container that they are in.

3:08Okay, but what about their compressibility? Humans cannot compress air that much. If you use machines, you can compress air a lot more. For example, if you consider the air inside the scuba dive tank, you would see the air is so compressed that, you know, it can actually fill up the volume of a telephone booth.

3:28That's how much air is compressed in a scuba dive tank. I mean, that's how much you can compress air using machines. So they are highly compressible. Gases are compressible. So that's about it. So, to summarize, we have three states of matter: solids, liquids, and gases.

3:46And what's the difference between them? Well, in solids, particles are completely packed together. They can wiggle around, but they cannot move at all. In liquids, they can sort of move, but they're still kind of close together. But when it comes to gases, well, they're completely free from each other, and they can completely, freely move about.

4:02What about their volumes? Well, solids and liquids have a fixed volume but gases don't. They take the volume of the container. What about their shapes? Well, solids have a fixed shape. Liquids don't. They take the shape of the container. Even gases don't. They take the shape of the container.

4:17And what about their compressibility? Well, solids and liquids are pretty much incompressible, so you can't compress them, right? However, gases can be easily compressed.