States of Matter

Try This!

Find a solid object in your classroom. Use your senses of sight and touch to describe the object to a classmate.

The pencils stay the same shape whether they are in the cup or the pencil case.

There are three states or forms of matter – solids, liquids and gases. The properties of each state of matter is different.

The objects around you, such as your desk, books and pens are solids. Solids are matter that have a fixed shape and volume. This means the shape and volume of a solid does not change when it is placed in different containers. If you take a book and move it between different containers, its shape and volume does not change. A rock is an example of a solid. Take a small rock and place it on a hard surface. Use you foot to press down on the rock. Notice that pressing down on the rock does not change its shape or volume. Solid matter cannot be compressed and does not change shape easily.

What are the properties of solids, liquids and gases?

Properties of Solids

AB Activities 10.2 – 10.3

Properties of Liquids

Water, milk and cooking oil are examples of liquids. Like solids, liquids have a fixed volume. This means the amount of space taken up by a liquid always stays the same. Try pouring some water into a measuring cup and measure its volume. Pour the water into a measuring cylinder and measure its volume again. You’ll notice that the volume of the water does not change when placed in different containers. Like solids, liquids cannot be compressed. Unlike solids, liquids do not have a fixed shape. The shape of a liquid depends on the container it is in. When you pour some milk from a carton or bottle into a glass, the shape of the milk changes, but the volume of the milk remains the same.

In what ways is a liquid different from a solid?

Try This!

Use containers of different sizes to demonstrate how a liquid flows to take the shape of its container. How can you find out if the volume of the liquid changes?

Think Deeply

What will happen to the shape and volume of the air inside a balloon when the balloon is popped?

Properties of Gases

Gases are matter that can change in both shape and volume. You can’t always see gases, but they are all around you. The air you breathe is a gas. The water vapor released from a boiling kettle is also a gas. When you blow up a balloon, you are filling the balloon with air from your lungs. You can press softly on the expanded balloon and change the shape of the gas inside. When you let go of the balloon, the gas spreads out in all directions and fills the room. Its volume changes. We can also compress a gas to reduce its volume, like when adding air to a scuba tank. Inside the scuba tank, the compressed air takes up much less space.

Use the pictures to compare and contrast the properties of the different states of matter.

AB Activity 10.4