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Do you know what water, air, and rocks all have in common?
They are made of matter!
Matter is someting that takes up space. Now, you might be wondering why they all look so
different if they are made of the same thing, but the truth is that EVERYTHING around you
is made of matter, just in different shapes and forms. Matter is made of tiny particles
called atoms.
Matter can be grouped into three main states: solid, liquid, or gas. To figure out which
state of matter something is in, we need to examine its properties. A property is the
way that something is, that we can measure.The physical properties we will look at to determine
state of matter are shape, mass, and volume. Mass is the amount of matter in an object.
Volume is how much space that matter takes up.
Solids are easy to recognize. Rocks, apples, pencils, and plants are all examples of solid
objects. A solid object has a definite shape that doesn't change when you move it or put
it in a container. They also have a consistent mass and volume. This is because the atoms
in a solid object are packed closely together so they do not move around. A solid will change
shape only if forced, for instance, if it is broken or smashed.
If you look around, you can find many examples of solid objects.
Liquid is the next state of matter. Liquids have a definite volume and mass, but they
do not have a definite shape. The atoms in liquid are still close together, but unlike
the atoms in a solid, they can move around. This allows the matter in a liquid to flow.
Because liquids don't have their own shape, they take their shape from their containers.
The same amount of liquid may look very different in a glass and spilled on the floor.
You can find examples of liquids around you, too. Water, milk, and juice are just some
of the liquids you might find.
The third state of matter is gas. Gasses have a definite mass, but they do not have a definite
shape or volume. Like liquids, gasses take the shape of their containers. Unlike liquids,
gasses will spread out to completely fill the container they are in. If a gas is not
in a container, it will keep spreading out indefinitely. This is because the atoms in
a gas are farther apart than atoms in a solid or a liquid, and so they can move freely.
The air you breathe is an example of a gas. You might have noticed that you can't really
see air. Often gasses are invisible - but they are still there. There are many different
types of gasses in earth's atmosphere, like oxygen, nitrogen, carbon dioxide, helium,
and water vapor.
Sometimes matter can change from one state to another. Water is a very good example of
this. When water is frozen into ice, it is a solid. When it melts back into water, it
is a liquid. When water evaporates into water vapor, it becomes a gas.
Matter in all its states is everywhere. See if you can find solids, liquids, and gasses
around you!