Grade by Grade
C. Matter and Energy · Properties of and Changes in Matter

What Is Matter? Mass and Volume

C2.1 A1.2 A1.5About 40 minutes
Learning goals
  • I can explain that matter is anything that has mass and takes up space.
  • I can measure mass in grams and kilograms with a scale.
  • I can measure volume in millilitres, and find the volume of a rock by displacement.
  • I can tell which things are matter and which are not.

Words to know

matter
Anything that has mass and takes up space. Solids, liquids and gases are all matter.
mass
The amount of matter (stuff) in something. We measure mass in grams (g) and kilograms (kg).
volume
The amount of space something takes up. We measure the volume of liquids in millilitres (mL) and litres (L).
displacement
When an object goes into water, it pushes water out of the way, so the water level rises. The rise equals the object's volume.
cubic centimetre (cm³)
The space taken up by a cube 1 cm long, 1 cm wide and 1 cm high. 1 cm³ is the same volume as 1 mL.

Remember from Grade 2

In Grade 2 you learned about solids and liquids, and you found out that air is real stuff: it takes up space and has mass. You also learned that water can be ice, liquid water or water vapour. In Grade 5 you will use the scientist's word for all of this stuff: matter.

Is it matter?

Look around you. Is your pencil matter? The milk in your glass? The air inside a soccer ball? What about your shadow, or the sound of a dog barking?

By the end of this lesson you will be able to answer every one of these questions, and explain how you know.

What is matter?

Matter is everything that has mass and takes up space.

  • Your body is matter.
  • Water, juice and maple syrup are matter.
  • Air, steam and the gas in a helium balloon are matter, even though you can't always see them.

Scientists say matter has mass and occupies volume. Let's learn what those two words mean.

A red helium balloon floats above a kitchen table with a glass of milk, a small jug of maple syrup and a yellow pencil.
Everything in this picture is matter: the solid pencil, the liquid milk and syrup, and even the invisible helium gas inside the balloon. Each one has mass and takes up space. AI-generated image

Mass: how much stuff

Mass is the amount of matter in something. A big rock has more mass than a pebble made of the same kind of rock.

We measure mass with a scale or a balance. The units are:

  • grams (g) for light things: a paper clip has a mass of about 1 g.
  • kilograms (kg) for heavier things: a 1 L carton of milk has a mass of a little more than 1 kg.

1 kg = 1000 g.

Volume: how much space

Volume is the amount of space something takes up.

  • For liquids, we use a measuring cup. The units are millilitres (mL) and litres (L). 1 L = 1000 mL.
  • For solids, one way is to measure how much water they push aside. This is called displacement.
  • Gases take up space too. When you blow up a beach ball, the air you blow in takes up space and makes the ball bigger.

A cube that is 1 cm on each side has a volume of 1 cubic centimetre (1 cm³). That is the same as 1 mL.

200 mL260 mLbefore: water onlyafter: water + rock
Before: 200 mL of water. After the rock is added, the water reads 260 mL. The rock pushed aside 60 mL of water, so its volume is 60 mL (60 cm³).
Worked example

Let's find a rock's volume by displacement

Aidan has a rock that is too bumpy to measure with a ruler. How can he find its volume?

  1. Pour water into a measuring cup and read the level: 200 mL.
  2. Gently lower the rock into the water so it is completely underwater and no water splashes out.
  3. Read the new level: 260 mL.
  4. Subtract: 260 mL − 200 mL = 60 mL. The rock pushed aside 60 mL of water.

The rock's volume is 60 mL, which is the same as 60 cm³.

Don't mix them up

Mass and volume are different. A beach ball and a bowling ball can be about the same size (similar volume), but the bowling ball has much more mass. A big puffy pillow has a large volume but not much mass.

What is NOT matter?

Some things are real, but they are not matter, because they have no mass and don't take up space:

  • light (sunlight, a rainbow, a lamp's glow)
  • sound (music, a dog's bark)
  • heat (thermal energy)
  • a shadow (just a place where light is blocked)
  • thoughts, feelings and ideas

Light, sound and heat are forms of energy. You learned about light and sound in Grade 4. Energy can move through matter, but it is not matter itself.

Does it havemass?Does it take upspace?MATTERapple, air, steamyesyesnonoNOT mattersunlight, a song, a shadow, a feeling
Two questions sort anything: Does it have mass? Does it take up space? Only if the answer to both is yes, it is matter.
Worked example

Let's sort: matter or not matter?

Sort these: an apple, the air in a sealed bag, sunlight, the song on the radio, steam from a kettle, a happy feeling.

  1. Ask two questions for each thing: Does it have mass? Does it take up space?
  2. Apple: has mass and takes up space → matter.
  3. Air in a bag: it puffs the bag out, so it takes up space; air has mass → matter.
  4. Steam: it is water as a gas (water vapour). The little white cloud you can see above a kettle is tiny drops of liquid water. Gas or tiny drops, both have mass and take up space → matter.
  5. Sunlight, a song, a happy feeling: no mass, take up no space → not matter.

Matter: apple, air in a bag, steam. Not matter: sunlight, song, happy feeling.

Just for fun

Why did the measuring cup get asked to leave the library?

Its volume was way too high!

MatterNot matter
a rocklight from a lamp
orange juicethe sound of a drum
the air in a tirea shadow
snowheat from the Sun
your bodya dream
Matter has mass and takes up space. Energy and ideas do not.
Hands-on activity

Matter detective at home

You need: a kitchen scale, a measuring cup with mL marks, water, a clean rock that fits in the cup (or another small object that sinks and can get wet, like a metal spoon or a toy figure), a clear plastic cup, a dry tissue, a large bowl or a sink filled with water, a pencil and paper.

Part 1: Mass

  1. Choose 3 objects (for example an apple, a spoon and a book). Predict their order from least to most mass.
  2. Measure each one on the scale. Record the mass in grams.
  3. Was your prediction right? Did the biggest object always have the most mass?

Part 2: Volume by displacement

  1. Pour water into the measuring cup to a line you can read easily (like 200 mL). Record it.
  2. Gently lower the rock in until it is completely underwater. Record the new level.
  3. Subtract to find the rock's volume. Try a second object.

Part 3: Air takes up space

  1. Stuff the dry tissue into the bottom of the clear cup so it won't fall out.
  2. Turn the cup upside down and push it straight down into the bowl of water. Don't tip it.
  3. Lift it straight up and feel the tissue.

What to look for: In Part 3 the tissue stays dry. The cup was full of air, and the air took up space, so the water could not get in. That is evidence that air is matter. Share your results with a family member using the words mass, volume and matter.

Safety: wipe up spills right away so nobody slips. Keep small objects away from little brothers and sisters.

Your turn

1

What is matter?

2

Is water matter? How do you know?

3

Name two things that are not matter.

4

What tool measures mass? Name the two units we use.

5

A measuring cup has 300 mL of water. After a stone goes in, it reads 340 mL. What is the stone's volume?

6

Why did the tissue stay dry in the upside-down cup?

More practice: warm-up

1

Matter or not matter: a pencil?

2

Matter or not matter: the sound of a whistle?

3

Matter or not matter: steam?

4

Matter or not matter: milk?

5

How many grams are in 1 kilogram?

More practice: on your own

1

A bowling ball and a beach ball are about the same size. Which has more mass? Which has more volume?

2

Why is air matter, even though you usually can't see it?

3

Is a shadow matter? Explain.

4

Liam pours 250 mL of juice from a tall glass into a wide bowl. Is there still 250 mL? Explain.

5

The water in a measuring cup is at 150 mL. Liam drops in 3 identical marbles and the level rises to 165 mL. What is the volume of one marble?

Challenge

1

Why can't you find the volume of a sugar cube by putting it in water?

2

A cork floats. How could you use displacement to find its volume?

3

Maya says, "This empty 1 L bottle has nothing in it." Is she right? Explain.

Check your understanding

Quiz

1.

Matter is anything that...

2.

Which of these is not matter?

3.

Which unit do we use to measure mass?

4.

Volume tells us...

5.

Water in a cup reads 100 mL. A rock is added and it reads 130 mL. What is the rock's volume?

6.

In the tissue test, the tissue stayed dry because...

For parents and teachers

Big idea: Ontario Grade 5 expectation C2.1 asks children to describe matter as everything that has mass and occupies volume. The activity also practises measuring and recording (A1.2) and sharing results (A1.5).

How to help: Use your kitchen scale and measuring cups together. Ask "Is it matter? Does it have mass? Does it take up space?" about everyday things, including tricky ones like steam, smoke (matter: tiny bits of solid and gas) and sunlight (not matter).

Common difficulties:

  • Thinking only things you can see or hold are matter. Air and steam are matter too.
  • Mixing up mass and volume. Compare a pillow and a book: big volume, small mass, and the other way around.
  • Displacement errors: the object must be completely underwater, and no water should splash out. Read the level at eye level.

Safety: wipe up spills. Keep marbles and small objects away from young children (choking hazard).