States of Matter — Answer Key
Part A: Fill in the Blank
Write the missing word or number on each line.
1. Fog is made of tiny water droplets hanging in the air.
Fog is a cloud at ground level made of very small liquid water droplets.
2. Rain is liquid water that falls from clouds.
Rain drops are liquid water, so they flow and soak into the ground.
3. Snow is frozen water, so it is in a solid state.
Snowflakes are tiny solid ice crystals that keep a shape.
4. Wind is moving air, which is a mix of gases.
Air is made of gases, and when it moves quickly we feel wind.
5. Hail is solid because it is hard balls of ice.
Hail forms as solid ice in storm clouds and keeps its shape when it lands.
6. A cloud is made of tiny water droplets high up in the sky.
Clouds are made of millions of tiny liquid droplets or ice crystals.
7. Water vapor is an invisible gas that rises from puddles.
Water vapor is water in gas form and is always present in the air.
8. When morning fog warms up, the droplets turn into water vapor.
Fog droplets evaporate into water vapor when the sun heats them up.
9. Frost on a window is solid ice crystals formed from cold air.
Frost is frozen water vapor that sticks to cold surfaces as solid crystals.
Part B: Matching
Match each item on the left to the correct answer on the right.
1. Match each item to its correct answer.
Fog
→ tiny liquid water droplets in the air
moving air made of gases
Rain
→ liquid water falling from clouds
tiny liquid water droplets in the air
Snow
→ solid ice crystals falling down
liquid water falling from clouds
Wind
→ moving air made of gases
solid ice crystals falling down
Fog is liquid droplets, rain is liquid water, snow is solid ice, and wind is gases in motion.