Grade 4 · Science · Unit 4 of 6
Particles & Mass
Matter has mass and space
What your child practises
Solids, liquids and gases at the particle level, how temperature changes particle speed, and conservation of mass (melting or dissolving doesn't change the total mass), with some adding of grams.
BC Curriculum learning standard: Matter has mass and takes up space; effect of temperature on particle movement; conservation of mass
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
Sam puts 650 g of water in a closed container in the freezer. What is the mass of the ice?
⚖️answer boxg
Show answer
650 g
Hint: Freezing changes a liquid into a solid, but the mass stays the same when nothing is added or taken away.
Question 2
What happens to particles when they are heated?
🔥- They move slower
- They stop moving
- They move faster
- They disappear
Show answer
They move faster
Hint: Heat gives particles more energy, so they move faster and spread apart.
Question 3
In which state of matter are the particles packed tightly together?
- 💧liquid
- 🧱solid
- 💨gas
Show answer
🧱 solid
Hint: In a solid, particles are packed tightly and just wiggle in place. That's why solids keep their shape.
Question 4
In which cup are the water particles moving the fastest?
Cups of water Cup Temperature A 12 °C B 50 °C C 65 °C - Cup C
- Cup A
- Cup B
Show answer
Cup C
Hint: Heat makes particles move faster. Find the hottest cup.
Question 5
In a gas, the particles…
💨- stay locked in place
- never move at all
- spread far apart and move freely
- are packed tightly in rows
Show answer
spread far apart and move freely
Hint: Gas particles zoom around and spread out to fill whatever space they are in.
Question 6
Solid, liquid or gas? Tap an item, then tap its basket.
Sort into: 🧱 solid · 💧 liquid · 💨 gas
- ♨️steam from a kettle
- 🥛milk
- 🌧️rain drops
- 🧊ice cube
- ✏️pencil
- 🌬️the air you breathe out
Show answer
🧱 solid: ice cube, pencil · 💧 liquid: milk, rain drops · 💨 gas: steam from a kettle, the air you breathe out
Hint: Solids keep their shape. Liquids flow and take the shape of their container. Gases spread out to fill any space.