States of Matter — Answer Key
Part A: Fill in the Blank
Write the missing word or number on each line.
1. When ice warms up, it melts into water.
Warming a solid enough turns it into a liquid. This change is called melting.
2. When water gets very cold, it freezes into ice.
Cooling a liquid enough makes it into a solid. This change is called freezing.
3. When water gets very hot, it boils into steam.
Heating a liquid enough turns it into a gas. This change is called boiling.
4. Melting turns a solid into a liquid.
Melting is the change from solid to liquid, like ice to water.
5. Freezing turns a liquid into a solid.
Freezing is the change from liquid to solid, like water to ice.
6. Boiling turns a liquid into a gas.
Boiling is the change from liquid to gas, like water to steam.
7. A popsicle is juice that has been frozen.
Cooling the juice turns it into a solid popsicle by freezing.
8. A chocolate bar left in the sun will melt.
Heat from the sun changes the solid chocolate into a soft liquid shape.
9. Heat and cold can change the state of matter.
Adding or taking away heat can move matter between solid, liquid, and gas.
Part B: Matching
Match each item on the left to the correct answer on the right.
1. Match each item to its correct answer.
melting
→ Solid to liquid
Solid to liquid
freezing
→ Liquid to solid
Liquid to solid
boiling
→ Liquid to gas
Liquid to gas
cooling steam
→ Gas back to liquid
Gas back to liquid
Melting is solid to liquid, freezing is liquid to solid, boiling is liquid to gas, and cooling steam is gas back to liquid.