# States of Matter

## What is Matter?

Matter is everything around you. Atoms and molecules are all composed of matter. Matter is anything that has mass and takes up space of an object. If you are new to the idea of mass, it is the amount of stuff in an object. We talk about the difference between mass and weight in another section of science. Matter is sometimes related to light and electromagnetic radiation coming from the sun. We weigh matter by using mass, volume and density. Mass is the amount of stuff in a object, volume is how much space it takes up inside an object and density is
Even though matter can be found all over the Universe, you will only find it in a few forms on Earth. We cover five states of matter on earth. Each of those states is sometimes called a phase. There are many other states of matter that exist in extreme environments like outer space . Scientists will probably discover more states as we continue to explore the Universe around us.

You should know about solids, liquids, gases, plasmas, and one state called the Bose-Einstein condensate (BEC).What makes a state of matter? It's about the physical state of the molecules and atoms.

## 5 changes of state in matter

All matter can move from one state to another. It may require extreme temperatures or extreme pressures, but it can be done. Sometimes a substance doesn't want to change states. You have to use all of your tricks when that happens. To create a solid, you might have to decrease the temperature by a huge amount and then add pressure. For example, oxygen (O2) will solidify at -361.8 degrees Fahrenheit (-218.8 degrees Celsius) at standard pressure. However, it will freeze at warmer temperatures when the pressure is increased.

Solid to Liquid
Liquid to Solid

Liquid to Gas

Gas to Liquid
Solid to Gas

Gas to Solid

## Chemistry term

Fusion/Melting
Freezing
Vaporization/Boiling
Condensation
Sublimation
Deposition

## Solid to Liquid and Back to Solid

Imagine that you are a solid. You're a cube of ice sitting on a counter. You dream of becoming liquid water. You need some energy. Heat is probably the easiest energy you can use to change your physical state. The atoms in a liquid have more energy than the atoms in a solid.

There is a special temperature for every substance called the melting point. When a solid reaches the temperature of its melting point, it can become a liquid. For water, the temperature needs to be a little over zero degrees Celsius (0oC) for you to melt.

If you were salt, sugar, or rock, your melting point is higher than that of water. How do you know that fact? If their melting points were lower, they would also be liquids at room temperature. The reverse of the melting process is called freezing. Liquid water freezes and becomes solid ice when the molecules lose energy.

## Solid to Gas and Back to Solid

You are used to solids melting and becoming liquids. Some of you may have also seen a solid become a gas. It's a process called sublimation. The easiest example of sublimation might be dry ice. Dry ice is solid carbon dioxide (CO2). Amazingly, when you leave dry ice out in a room, it just turns into a gas. Have you ever heard of liquid carbon dioxide? It can be made, but not in normal situations. Coal is another example of a compound that will not melt at normal atmospheric pressures. It will sublimate at very high temperatures.

Can you go from a gas to a solid? Sure. Deposition occurs when a gas becomes a solid without going through the liquid state of matter. Those of you who live near the equator may not have seen it, but closer to the poles we see frost on winter mornings. Those little frost crystals on plants build up when water vapor from the air becomes a solid on the leaves of plants.