Ice sublimating to water vapor

AI Thread Summary
In a vacuum, ice can sublimate directly to water vapor when the temperature is raised slightly above 0 degrees Celsius, without passing through a liquid phase. The vapor pressure of water exists at all temperatures above absolute zero, meaning sublimation can occur as long as the temperature is increased. Maintaining a vacuum prevents the accumulation of vapor pressure, which influences the sublimation process. The discussion highlights the relationship between temperature and vapor pressure, emphasizing that sublimation is possible under these conditions. Ultimately, ice can transition directly to gas in a vacuum when temperature conditions are met.
bobkolker
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Suppose an ice cube is in a vessel and it is at a temperature slightly below 0 degrees Cesius. Suppose further that the inside of the vessel is a vacuum. If the temperature of the vessel is increased to slightly above zero Celsius and the vacuum is maintained would the state change in the ice cube be from solid to gas with no liquid in in between phase?

Bob Kolker
 
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What do you think would happen?
 
Are you saying that there is perfect vacuum maintained in the container? Why do you feel like you need to increase the temperature to get the ice to evaporate?
 
Chestermiller said:
Are you saying that
I suspect that the OP has been quoted from a textbook.He's just looking for the answer.
 
There is a saying (worth memorizing and repeating), "vapor pressure (in equilibrium) is dependent upon temperature alone."

Suffice it to also know that the vapor pressure of water is above zero at any temperature except for absolute zero itself (and absolute zero isn't achievable). In other words, the vapor pressure of water (whether it be solid ice or liquid water) is never actually zero.

Now if the vacuum is maintained, such that the vapor pressure never has a chance to accumulate, what is the ultimate fate of the ice at any given temperature?
 
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