Kathleen Weidner Zoehfeld - What Is the World Made Of?: All About Solids, Liquids, and Gases

H ave you ever seen anyone walk through a wall?

Did you ever drink a glass of blocks?

Have you ever played with
a lemonade doll, or put on
milk for socks?

Walls and blocks, dolls and socks. Milk and lemonade.
Rocks and trees. All of these things are made of matter.

The air in the breeze that blows the leaves. Water flowing
in the creek. Everything on earth is made of matter.
Lucky for us, its easy to tell that not all matter is alike.

Matter comes in three states. It can be solid, liquid, or gas.

Walls and blocks and
socks are SOLIDS .

Milk and lemonade and
water are LIQUIDS .

The air you breathe is a GAS .

Some solids are hard and some are soft. But all solids hold
their shape unless you do something to change them.
A wooden block is hard. You can push it and pull it and
squeeze it. If your baby brother pounds it with his toy truck,
it may chip or break. But then the broken pieces will hold
their shapes.

Modeling clay is soft. You can roll it out flat, like a
pancake, or squeeze it into a ball. You can cut it with a knife
or scissors. But if you leave it alone, it will hold whatever
shape it is in. It is a solid.

Liquids have no shape. You pour a glass of milk for your
little sister, and the milk takes on the shape of the glass.
If she knocks it over, the milk spreads out on the tabletop.
It flows over the edge like a waterfall. It drips and spatters on
the floor. Milk is not round or square it has no shape at all.

Liquids can be thick, like a milkshake,
or thin, like water. They can feel slippery,
like cooking oil, or sticky, like maple
syrup. But all liquids can be poured.
And all liquids take on the shape
of whatever they are in.

Gases have no shape either. Like air, most gases are
invisible you cannot see them. But you can feel them.
Hold out your arms and spin. You can feel the air move
against your skin. Air fills up all the space around you.

Gases spread out to fill up any container they are in,
no matter how big. Ask a grown- up if you can borrow
a bottle of perfume. Then ask someone to be your
assistant.
Go into a room and close all the doors and windows.
Stand in one corner and have your assistant stand in the
opposite corner. Open the bottle and wave it around gently.
Can your friend smell the perfume? How long does it
take before she can smell it?
When you open a bottle of perfume, some of the gas in
the perfume escapes. In a few minutes the gas will spread
out to every corner of the room.