Water Molecules & States of Matter
When water vapor cools and changes into a liquid.
What is condensation?
What happens during evaporation?
Liquid water heats up and changes into water vapor.
What is the atmosphere?
The layers of gases surrounding Earth.
What is water vapor?
Water in its gas form.
What energy source drives the water cycle?
The Sun.
Tiny particles that make up all matter.
What are molecules?
What stage of the water cycle forms clouds?
Condensation.
Which layer of the atmosphere do we live in?
The troposphere.
Where can water vapor be found in the atmosphere?
Mostly in the troposphere.
Why does condensation often happen on cold surfaces?
Water vapor cools and changes to liquid.
In which state are water molecules closest together—solid, liquid, or gas?
Solid (ice)
What is runoff?
Water flowing over the ground into rivers or oceans.
In which layer does most weather occur?
Troposphere.
What two things cause water to evaporate faster?
Heat and wind.
How does gravity affect the water cycle?
It pulls precipitation down and helps water flow to oceans.
Name the 3 main states of matter.
Solid, liquid, gas.
What causes precipitation to fall from clouds?
There becomes too many water droplets, they get too heavy, and gravity pulls them down.
Which layer is in the middle of the five layers?
Mesosphere.
Why can’t we always see water vapor?
Because it is invisible gas.
Explain the difference between evaporation and boiling.
Evaporation happens at any temperature; boiling happens when water gets hot enough to bubble.
How do molecules move in water vapor compared to liquid water?
They move faster and spread farther apart.
Name the 3 main stages of the water cycle.
Evaporation, condensation, and precipitation
Name the 5 layers of the atmosphere in order (bottom to top).
Troposphere, stratosphere, mesosphere, thermosphere, exosphere
What must water vapor do to form clouds?
Cool and condense.
Describe what happens to molecules during condensation.
They slow down and move closer together as gas becomes liquid.