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Ch.11 - Liquids and Intermolecular Forces
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All textbooksBrown 14th EditionCh.11 - Liquids and Intermolecular ForcesProblem 83b

Chapter 11, Problem 83b

(b) A flask of water is connected to a vacuum pump. A few moments after the pump is turned on, the water begins to boil. After a few minutes, the water begins to freeze. Explain why these processes occur.

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Hey, everyone were asked which of the following explains how the body is cooled down while sweat evaporates. So it looks like we're talking about evaporation here and we know that evaporation is the conversion from a liquid to a gas. And since these molecules are absorbing heat, we know that evaporation is going to be endo thermic. So our answer here is going to be a evaporation is endo thermic. The heat required for the process is absorbed from the surroundings, which is the body. And we know that going from a liquid to a gas is in fact an end of thermic reaction. So I hope this made sense and let us know if you have any questions.
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