States of matter

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States of Matter

All matter exists in 4 stages. We call these the States of matter.

Solid, Liquid, Gas and Plasma

Within our body matter exists solid, liquid and gas states.

Before we start talking about states of matter, you first need to understand that all matter is made of particles. These particles are Constantly in motion, wether they are a liquid, gas, plasma or even a solid, they are always moving.

The amount of movement and energy varies between states.

Look at an ice cube. This is a solid. You can’t compress a solid and it won’t flow. The only way we can change the shape of a solid is if we apply force to it.

If we look down to the atomic level, we see that molecules in a solid touch each other and vibrate on the spot. This explains why we can’t compress a solid.

Look at some water. This is a liquid state. We still can’t compress liquids, but we can pour them. They will take the shape of the container they are in.

In liquids the particles have more energy than a solid. They slide over each other and touch their neighbours. Although they have more freedom than solids, they still stay close to the other particles.

Look at steam. This is a gas state. We can easily compress gas, in fact the breaks in cars depend on gasses. We can even pour it, meaning gas is a fluid (not liquid) like water.

The particles are far apart and move much faster. As the liquid is heated the particles gain more energy and being to take up more space.

Eventually they break free completely from the forces which hold them together. This is called Vaporisation.

It was long thought that there was only 3 states of matter, Solid, liquid and gas. However after studying the stars, scientists discovered a fourth state.

Plasma

This is ironic because plasma actually makes up 97% of the visible universe.

As we add more energy to a solid structure, it eventually becomes a liquid. Add more energy and it becomes a gas. Add even more energy and it become a plasma.

So what happens to the particles in the substances? The particles them selves don’t change (H2O is in water, ice and steam), but their arrangement and movement changes in each state.