States of Matter
In this video you are going to learn:
* What the three states of matter are
* Some examples of each state of matter
* The characteristic properties of the three
states of matter.
The three states of matter are Solid, Liquid
and Gas.
Let us look at solids. An example of a solid
is your computer. The properties of solids
depend on how the particles in solids are
packed. In a solid the particles are closely
packed in fixed positions and cannot move
anywhere. So, solids are rigid, cannot be
squashed or compressed, have a fixed shape
and a fixed volume. They cannot flow.
Now let us look at liquids Ð an example of
a liquid is water. Just as with solids, the
properties of liquids depend on how the particles
in liquids are packed. In a liquid the particles
are again closely packed but not as closely
packed as in solids - so this means the particles
in liquids can move around each other. So,
liquids are not rigid, but because their particles
are closely packed as in solids they cannot
be squashed or compressed. They do not have
a fixed shape but they do have a fixed volume.
Beware with that one as many students think
because liquids do not have a fixed shape
they do not have a fixed volume either Ð
but they are wrong. If someone orders a pint
of beer they cannot make it 2 pints by pouring
it into different containers. As you know,
liquids can flow.
Finally, let us look at gases Ð an example
of a gas is helium Ð this is the gas in party
balloons because it is less dense than air
and unreactive. Again, as with solids and
liquids, the properties of gases depend on
how the particles in gases are packed. Unlike
solids and liquids the particles in gases
are not closely packed Ð they are far apart.
As a result gases are not rigid and can be
squashed or compressed. They do not have a
fixed shape nor fixed volume Ð they fill
the whole space they are in.
