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W
hat happens to all that water in the air? As long as the air stays
warm, the water stays in the air as water vapor. Warmth (heat)
is
energy
. As long as the water vapor has a lot of energy in the
form of heat, it continues to exist as a gas.
But if the air cools, things change. As the air cools, the water vapor
condenses
. It changes from a gas into a liquid. When invisible water
vapor in the air condenses, the water becomes visible again. Clouds are
made of the tiniest droplets of liquid water that have condensed from
the air.
Condensation
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