# I Ice sublimating to water vapor

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1. Mar 10, 2016

### bobkolker

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

2. Mar 10, 2016

### DaveC426913

What do you think would happen?

3. Mar 11, 2016

### Anand Sivaram

4. Mar 12, 2016

### Staff: Mentor

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. Mar 12, 2016

### DaveC426913

I suspect that the OP has been quoted from a textbook.He's just looking for the answer.

6. Mar 13, 2016

### collinsmark

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?