States of Matter — Answer Key
Part A: Fill in the Blank
Write the missing word or number on each line.
1. Particles in a liquid can slide and flow past each other.
Liquids flow because their particles slide past each other, allowing them to be poured.
2. When you heat butter, it melts from a solid to a liquid.
Heat from the flame causes the solid wax to melt and turn into a liquid.
3. Putting water in a freezer causes it to freeze.
Freezing is the process where a liquid turns into a solid when enough heat is removed.
4. Steam rising from a pot is water in the gas state.
Water vapor is the gas form of water — its particles are spread far apart and move very quickly.
5. A solid has a definite shape because its particles are fixed.
Solids have a fixed shape because their particles are tightly packed and vibrate in place.
6. When a puddle dries up, the water has evaporated.
The sun's heat causes the liquid water in the puddle to evaporate and turn into water vapor in the air.
7. Dew on grass in the morning forms through condensation.
Condensation occurs when gas particles slow down, cool off, and come together to form a liquid.
8. Matter is anything that has mass and takes up space.
Gas particles have a lot of energy and move in all directions, expanding to fill whatever space is available.
9. An ice cube placed in the sun will melt into liquid water.
Butter is a solid that melts when heated — it changes from a solid to a liquid.
Part B: Matching
Match each item on the left to the correct answer on the right.
1. Match each item to its correct answer.
Evaporation
→ Liquid changes to gas
Has no definite shape or volume
Freezing
→ Liquid changes to solid
Liquid changes to gas
Condensation
→ Gas changes to liquid
Gas changes to liquid
A gas
→ Has no definite shape or volume
Liquid changes to solid
Evaporation is when liquid changes to gas, freezing is when liquid changes to solid, condensation is when gas changes to liquid, and a gas has no definite shape or volume.