In a very cold very dry climate will ice slowly evaporate??
It’s done that in my freezer.
Technically it will “sublimate,” but yes.
Yes. As has been said, the process is called sublimation, and is quite common. Sublimation is used in the process of freeze-dying.
Is there an optimum temperature or combination of ice and air temp for this affect?
One thing I learned on the Dope is that sublimation requires the same amount of energy as the two step process of melting and evaporation.
Generally, ice and snow sublimate (slowly) if the air temperature is below freezing and sunlight applies energy to the surface of the ice/snow.
In freeze drying, a partial vacuum is applied.
A phase diagram for water will show you the equilibrium amounts as a function of temperature and partial pressure.
In the case of sunlight providing energy would the snow pass through a short liquid phase?
It can go both ways. The ice and snow can melt and then evaporate, or the ice and snow can directly sublimate without going through the liquid phase. The latter generally requires colder air temperatures.
There are relatively few compounds that can sublimate. A couple of others are dry ice (Carbon dioxide) and elemental Iodine. The phenomenon is much more common in dry ice, which under ordinary circumstances, “melts” without ever leaving a trace of liquid.
Sometimes I feel like a little kid in a candy shop when I come on the Dope. I always get great answers to useless questions. I remember in my childhood asking questions like this and people looking at me like “You are really weird”. That was 60 years ago so I feel like I am getting a second chance. Thanks to all!
Not really. Maybe you mean under near-ambient conditions?
The process is sublimation. If the ice does this, it is said to sublime. Sublime is preferred over sublimate so as not to be confused with the psychological definition of sublimate.
Among physicists, the preferred term is “sublimate”. Psychologists might have a different meaning for that word, but they’re also not likely to be particularly concerned with phase changes in matter. I’m having a hard time thinking of a context where the two meanings of the term might cause confusion.
Right - this is much the same as saying that the gain in elevation from the base of a hill to its top is the same regardless of the route you travel.