Ugh! Look at that fancy title! But don't worry, this is just a simple theory to explain:
- What makes a solid a solid
- What makes a liquid a liquid
- And what makes gas a gas
Atoms are what now?
Just so you can understand this theory, just imagine that a particle is a football. Just in case you can't imagine it, our thoughtful team has provided a football for you.
Okay, perfect. Now, on the theory.
As you can see from the image, these are some of the football-particles in a solid. They are tightly packed, BUT they can still vibrate to and fro. They are hard to compress (squish) as the particles are very tightly packed together and can't get much more close to each other. As the particles are close together, it makes them dense (heavy for their size). Finally, they can't flow like a liquid because all they particles stay in their positions.
This may surprise you, but liquid particles are actually quite close together. It's just that they can move...
There are some forces of attraction between these particles - unlike the strong forces when it is a solid - and the particles are now free to move past each other. Liquids also aren't compressed easily - they may not always be the same shape, but they are always the same volume! They are quite dense, but not as dense as solids!
What do these particle-footballs look like for gases?
Wow! These are very far apart! With gases, there are weak forces of attraction between the particles, so they are very far apart. They don't keep a definite volume - they always expand to fill a container. They move very fast, and this can be used to explain...
Because the particles move so fast, they often bump into the edges of the container that they are in and each other. When they hit the wall of the container, it causes gas pressure! This is why the pressure increases in balloons and other inflatable thingies: because more gas particles = more bumping into walls = more pressure!
Heating up the gas makes them move faster, therefore creating more pressure.
Did you know...?
This is the reason that deodorant cans are labelled with 'don't heat up' as they are filled with gas, and if the air pressure gets to much, the EXPLODE! Awesome!
Have you ever wondered how a smell spreads around a room? Well, wonder no more - ScienceDorks to the rescue! Particles think a bit like you would if you were in a room full of people with BO - they want to spread out. The smell particles move from an area of high concentration (where the place is FULL of them), to a place where there is not as many i.e. the air. "But Dorks! I hear you squeal. "I thought that gases moved fast. So why do smell particles travel so slowly?"
Of course, there is a simple answer. They just bump into air particles slowing them or just stopping them altogether.
Got that? So go and make everyone's brain explode with your knowledge, and then RULE THE WORLD!