Question

Describe the conditions necessary for sublimation to occur.

Answer 1

To answer this question with specific values, you would need a phase diagram for the substance in question. In more general terms, the pressure needs to be lower than the pressure of the triple point, the substance must be present in its solid state, and the temperature must rise high enough to produce a gas.

Answer 2

Sample Response: Sublimation occurs because the atoms in a solid must gain enough energy to form a gas without passing through the liquid state.  Low air pressure and large amounts of energy, often in the form of heat, allow the atoms to move fast enough to overcome the attractive forces between them.