Ice sublimating to water vapor

In summary, the conversation discusses the state change of an ice cube in a vessel with a vacuum. It is mentioned that the vapor pressure of water is dependent on temperature and is never actually zero. Therefore, even if the temperature is slightly above zero Celsius, the ice cube will eventually evaporate due to the maintained vacuum.
  • #1
bobkolker
14
3
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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  • #2
What do you think would happen?
 
  • #4
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?
 
  • #5
Chestermiller said:
Are you saying that
I suspect that the OP has been quoted from a textbook.He's just looking for the answer.
 
  • #6
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?
 

FAQ: Ice sublimating to water vapor

1. How does ice sublimate to water vapor?

Ice sublimation is a process where the solid form of water, or ice, transitions directly into its gaseous form, or water vapor, without going through the liquid phase. This happens when the temperature and pressure conditions are such that the solid ice molecules have enough energy to break free from their bonds and become water vapor.

2. What factors affect the sublimation of ice?

The main factors that affect the sublimation of ice are temperature, pressure, and surface area. Higher temperatures and lower pressures favor sublimation, while larger surface areas of ice allow for a quicker sublimation process.

3. What is the purpose of using ice sublimation in scientific experiments?

Ice sublimation is commonly used in scientific experiments as a means of freeze-drying or dehydrating samples. This process removes water from the sample without the need for heat, which can potentially alter the sample's chemical or physical properties.

4. Can ice sublimation occur at room temperature?

Yes, ice sublimation can occur at room temperature, but it may take a longer time for the process to be noticeable. This is because at room temperature, the rate of sublimation is slower compared to lower temperatures.

5. Is ice sublimation reversible?

Yes, ice sublimation is reversible. This means that water vapor can also transform back into ice under the right conditions of temperature and pressure. This process is known as deposition.

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