Matter — Definition & Overview

What Is Matter?

Everything is made of matter. Atoms, molecules, air—even we are made of it. The word "matter" means anything that takes up space and has a mass.

Basically, matter makes up everything.

Imagine we cut a carrot in half. Now, imagine that we cut one of those pieces in half. We keep dividing the halves until, eventually, we cannot split the piece anymore. All we are left with is a pile of chemical substances.

Our strange little experiment shows us that everything is made up of small, subatomic particles. Everything that has a mass and volume (takes up space), everything that can be seen, touched, or even tasted is made of chemicals. Those chemicals are matter.

How Are Mass and Volume Represented?

Mass and volume can both be measured. Scientists use the metric system for measurements, not the imperial system (feet, pounds, etc).

The unit of mass is the gram, while the unit of volume is the liter. This is complementary to the imperial units of feet and cups/pints/gallons.

What Forms Can Matter Take?

Now, back to the matter at hand. Ha.

Matter exists in four different states: solid, liquid, gas, and plasma. States of matter are also commonly known as phases of matter.

• Solids have a fixed volume and shape.
• Liquids have a fixed volume but can take the shape of their container.
• Gasses have neither a fixed shape nor a fixed volume.
• Plasmas have similar properties to gasses.

Matter can switch between phases, as shown in the picture below. You've probably heard of some of these phase changes before, like freezing or melting. There are quite a few different kinds, though.

For example, solids can turn directly into a gas without ever being a liquid. Super strange, right? This is called sublimation and is very cool to watch.

Try to commit the picture above to memory. It shows all of the phase changes possible.

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$\color{#8925AE}{\text{Matter}}$ : Matter is anything that takes up space and has a mass

$\color{#8925AE}{\text{Phase}}$ : The phases of matter are a way to classify different properties of matter

Definition of Matter?

When we say that matter is anything that has mass and takes up space, we mean anything. Living and non-living things, things you can't see (like air), things that are huge (like planets and stars)...

If it's got mass and takes up space, it's matter.

Recall that mass can be measured using a scale or balance, and its units are in the gram family.

The whole idea of "taking up space" actually refers to volume. Volume is the amount of space something occupies. Its units are in the liter family.

So, if we wanted to be more scientific, we could say that matter is anything that has mass and volume.

States of Matter

Matter can exist in multiple forms, called states or phases. Under normal conditions on Earth, most matter is in one of three main phases: solid, liquid, or gas.

The picture above (in blue), shows differences among solids, liquids, and gases in terms of volume and shape. Here's what you need to know:

Key Vocabulary:

1. Matter
2. Mass
3. Volume
4. Phase
5. Solid
6. Liquid
7. Gas

(Video) What Is Matter?

by MrSimpleScience

This short video by MrSimpleScience defines what matter is, what it is made of, and what forms it can take.