Can Pressure Cause Water to Freeze at Room Temperature?

AI Thread Summary
The discussion centers on the relationship between pressure, temperature, and the states of water. It begins with the classic demonstration of boiling water at room temperature using a vacuum pump, prompting a question about whether raising temperature could cause water to freeze under high pressure. The conversation clarifies that while lowering pressure can change the state from liquid to gas by lowering the boiling point, it requires sufficient heat to vaporize the liquid. The concept of phase changes is further explored, emphasizing that while pressure affects the state of matter, simply raising temperature does not lead to freezing; rather, it is the density and arrangement of molecules under pressure that determine whether water can exist as a solid. The discussion highlights the complexities of phase transitions and the conditions necessary for them to occur.
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I imagine everyone here is familiar with the classic demonstration of making water boil at room temperature using a vacuum pump. Since lowering pressure changes the state from liquid to gas, can raising the temperature cause it to freeze? I know some about the difference in amounts of pressure it takes to undergo the change from liquid to gas and from liquid to solid, but is this even theoretically possible? Obviously it's not going to happen in a high school lab, but I was just wondering if there is a pressure at which water will freeze at room temperature.
 
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I'm not that knowledge on chemistry, but since I believe a liquid, solid, and gas are determined by how dense their molecules are, that under significant pressure that molecules would be packed so tightly in order to call it a solid.
 
pzona said:
Since lowering pressure changes the state from liquid to gas, can raising the temperature cause it to freeze?

I assume you mean pressure here. Yes, http://www.lsbu.ac.uk/water/images/phase.gif" .
 
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pzona said:
lowering pressure changes the state from liquid to gas

That's not exactly true. Lowering pressure you lower boiling point temperature - but it is not enough to vaporize the liquid. For that you still need to add enough heat to the system (enthalpy of vaporization). Boiling in the experiment you have described is possible thanks to water lowering its temperature, and soon stops in the lack of external heating.
 
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