Key Idea.
Section 1
Making the Invisible Visible
The air around you is full of invisible water vapor. But what happens when that gas cools down?
If water vapor touches a cold surface—like a glass of ice water—it loses heat. The gas molecules slow down and huddle back together. They turn back into liquid water. This process is called condensation.
Section 2
From Gas to Liquid
Condensation is the reverse of evaporation. During evaporation, molecules spread out to become a gas. During condensation, they clump together to become a liquid.
The droplets of water on the outside of a cold glass didn't leak from inside. They were pulled right out of the air! The cold glass caused the invisible water vapor in the room to condense into visible droplets.
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Section 1
Making the Invisible Visible
The air around you is full of invisible water vapor. But what happens when that gas cools down?
If water vapor touches a cold surface—like a glass of ice water—it loses heat. The gas molecules slow down and huddle back together. They turn back into liquid water. This process is called condensation.
Section 2
From Gas to Liquid
Condensation is the reverse of evaporation. During evaporation, molecules spread out to become a gas. During condensation, they clump together to become a liquid.
The droplets of water on the outside of a cold glass didn't leak from inside. They were pulled right out of the air! The cold glass caused the invisible water vapor in the room to condense into visible droplets.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter