Grade 5 · Science · Unit 6 of 10
Changes of State
Melting, freezing and more
What your child practises
Melting, freezing, evaporation and condensation at home and outdoors, and how matter absorbs or releases thermal energy when it changes state.
Saskatchewan Curriculum outcome: MC5.2 · reversible changes, including changes of state
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
A frozen juice bar drips in the sun. Which change of state is this?
- Freezing
- Condensation
- Melting
Show answer
Melting
Hint: A solid turns into a liquid when it absorbs thermal energy.
Question 2
Put these in order from LEAST thermal energy to MOST.
- ♨️Water vapour (gas)
- 🧊Ice (solid water)
- 💧Liquid water
Show answer
Ice (solid water) → Liquid water → Water vapour (gas)
Hint: A solid has the least energy and its particles move the least. A gas has the most.
Question 3
Which change of state needs thermal energy to be added?
- Freezing
- Evaporation
- Condensation
Show answer
Evaporation
Hint: A liquid needs extra energy to become a gas.
Question 4
Which of these is a physical change of state that is NOT water?
- Wax melting near a candle flame
- A match burning
- Bread being toasted
Show answer
Wax melting near a candle flame
Hint: A change of state keeps the same substance. Burning and toasting make new substances.
Question 5
What happens to particles of a liquid as they are heated and become a gas?
- They slow down and pack together
- They move faster and spread far apart
- They disappear
Show answer
They move faster and spread far apart
Hint: More thermal energy means faster-moving particles.
Question 6
On a cold morning, grass has tiny drops of water on it. What change of state made them?
- Melting of the grass
- Condensation of water vapour in the air
- Freezing of the air
Show answer
Condensation of water vapour in the air
Hint: Vapour cooled against the cold grass and became liquid.