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How does temperature affect the movment of water molecules?
Temperature causes water molecules to move more quickly, because
each individual molecule has more energy as it gets hotter (according
to Kinetic molecular theory). If you get water hot enough, the
molecules move so much that the hydrogen bonds that hold them together
start to break and the water becomes a gas ... water vapor.
p.s. Those hydrogen bonds are breaking and reforming all the time.
Some water molecules will fly off into the gas even at room
temperature, so there's always some water in the atmosphere. But when
the boiling point is reached, water molecules will leave the liquid and
go into the gas faster than they leave the vapor and stick to the
liquid even if the gas consists of pure water vapor. At that point the
liquid boils away. Mike W.
(republished on 07/24/06)
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