What's the matter?
Do you realize that everything in the universe is made of only
four basic types of matter! Your computer, a can of soda, the
air you breathe, and even the stars in the sky are all made of
one of these four basic types.
All matter is composed of billions of microscopic atoms.
These atoms combine to form molecules. Molecules are also
microscopic. There are billions of molecules that form to
create a tiny drop of liquid, a balloon full of helium, or the
eraser on a pencil.
Molecules are attracted to each other. Because of this
attraction, they are held directly next to each other. When
these molecules bind together, they form one of the four
states of matter. Depending on the state they are in,
molecules barely move, doing little more than vibrating in
place, as in a solid, or they can move in a quick, erratic
manner, bouncing against the area in which they are
contained, which happens with plasma.
To examine the attraction between molecules, think about
what happens to two magnets. If next to each other, the
opposite poles pull strongly at each other, and they stay side
by side. (solid) If you move the magnets a little bit apart, the
attraction, or pull, between them is not as strong. (liquid) If
you continue to move the magnets apart there is a much
weaker attraction. (gas) And finally, if you move the magnets
even farther away, there is barely any attraction left. (plasma)
Although all matter is in one of the four states at any given
time, these states are not necessarily permanent. Water is a
good example of changing states of matter. In a solid form,
water is ice. The molecules move slowly. Since they are so
close to each other, there is a strong attraction between all the
molecules, and they are kept tightly next to each other. All
molecules move, but since they are packed next to each
other so closely, molecules in a solid can do little more than
If heat is added to ice, it melts. It has changed states of matter.
It has gone from a solid to a liquid. It still contains the same
molecules, but they are now moving faster. This faster
movement sends the molecules farther away from each other,
and the attraction between them is not as strong as they were
in a solid. This allows a liquid to have a less rigid form and
flow to fit the shape of its container.
Finally, as water is heated even more and it evaporates, there
is only a weak attraction between the molecules, and they
wildly bounce off each other and float off in all directions.
This state of matter is called a gas.
Visit the following pages for more information on
the four types of matter.
changes of state
properties of matter
acids and bases
states of matter solid/liquid/gas
properties of matter
states of matter simulator
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Questions and comments: firstname.lastname@example.org last revised 6/2019