Year 4 Science Changing state and the water cycle: check-up and practice test questions

Method. Read the key idea in section 7.1.

1. Read the key idea. A solid that is heated and turns into a liquid is melting.
   melting
2. Write the answer.
   melting

Check. Melting is caused by heating. ✓

Method. Read the table in section 7.2.

1. Read the freezing row. Water freezes at 0 degrees Celsius.
   0
2. Write the answer.
   0

Check. Zero degrees is the freezing point of water. ✓

Method. Read the table in section 7.2.

1. Read the boiling row. Water boils at 100 degrees Celsius.
   100
2. Write the answer.
   100

Check. Boiling water becomes water vapour. ✓

Method. Read the table in section 7.3.

1. Read the minutes. The sunny windowsill took 30 minutes, the least.
   30
2. Write the answer.
   Sunny windowsill

Check. Warmer places dry things faster. ✓

Method. Subtract the warm room time from the cool room time.

1. Read the times. The cool room took 40 minutes, and the warm room took 20.
   40 and 20
2. Subtract. 40 minus 20 is 20.
   20
3. Write the answer.
   20

Check. Check: 20 plus 20 makes 40. ✓

Method. Read the key idea in section 7.4.

1. Read the key idea. A gas changing into drops of liquid by cooling is condensation.
   condensation
2. Write the answer.
   condensation

Check. Condensation forms drops. ✓

Method. Read the table in section 7.5.

1. Read the second stage. Condensation forms the clouds.
   clouds
2. Write the answer.
   condensation

Check. Clouds are made by condensation. ✓

Method. Read the table in section 7.5.

1. Read the third stage. Drops fall as rain, snow or hail.
   fall
2. Write the answer.
   precipitation

Check. Precipitation is water falling from clouds. ✓

Method. Use the pattern in the table.

1. Think about the pattern. Evaporation is faster when it is warmer.
   warmer
2. Decide. So a puddle dries faster in the warm place, and Ali is not right.
   warm place
3. Write the answer.
   No. Accept any reason that says evaporation is faster when it is warmer.

Check. The table shows that warm places dry things faster. ✓

Method. Think about the two changes.

1. Think about evaporation. Evaporation turns liquid water into water vapour.
   vapour
2. Think about condensation. Condensation turns the vapour back into liquid drops.
   back into drops
3. Write the answer.
   Accept any sentence that says evaporation turns water into vapour, and condensation turns the vapour back into drops.

Check. The two changes are opposites. ✓

Method. Read the key idea.

1. Read the key idea. A solid turning into a liquid by heating is melting.
   melting
2. Write the answer.
   melting

Check. Melting happens when a material is heated. ✓

Method. Read the key idea in section 7.2.

1. Read the key idea. Water boils at 100 degrees Celsius.
   100
2. Write the answer.
   100

Check. The boiling point of water is 100 degrees Celsius. ✓

Method. Read the key idea in section 7.2.

1. Read the key idea. Water freezes at 0 degrees Celsius.
   0
2. Write the answer.
   0

Check. Ice melts at the same temperature. ✓

Method. Read the key idea in section 7.4.

1. Read the key idea. A gas that cools and turns into a liquid is condensation.
   condensation
2. Write the answer.
   condensation

Check. Condensation is the opposite of evaporation. ✓

Method. Compare the two times.

1. Read the times. The sunny windowsill took 30 minutes, and the cool hallway took 90 minutes.
   30 and 90
2. Choose the faster. The shorter time is the faster one, which is the sunny windowsill.
   Sunny windowsill
3. Write the answer.
   Sunny windowsill

Check. The sunny windowsill was the warmer place. ✓

Method. Subtract the two times.

1. Read the times. The cooler room took 40 minutes, and the other room took 20.
   40 and 20
2. Subtract. 40 minus 20 is 20.
   20
3. Write the answer.
   20

Check. Check: 20 plus 20 makes 40. ✓

Method. Read the table of stages.

1. Read the order. The stages are evaporation, then condensation, then precipitation, then collection.
   in order
2. Write the answer.
   Evaporation; condensation; precipitation; collection

Check. Collection comes last, and the cycle starts again. ✓

Method. Read the key idea in section 7.3.

1. Read the key idea. Evaporation is when a liquid changes into a gas.
   evaporation
2. Write the answer.
   evaporation

Check. A puddle dries up by evaporation. ✓

Method. Think about the pattern.

1. Think about the heat. Evaporation is faster when it is warmer.
   warmer
2. Write the reason. So the puddle turns into water vapour faster on a hot day.
   faster
3. Write the answer.
   Accept any sentence that says evaporation is faster when it is warmer, so the puddle dries up faster on a hot day.

Check. Warmth speeds up evaporation. ✓

Method. Read the water cycle.

1. Read the stages. Evaporation turns the sea water into vapour, and condensation forms the clouds.
   forms the clouds
2. Name the stage. So the stage that forms clouds is condensation.
   condensation
3. Write the answer.
   condensation

Check. Clouds form by condensation. ✓