Which of the following phase changes only occurs in solids possessing vapor pressures above atmospheric pressure and at ambient temperature?

a. condensation
b. melting
c. sublimation
d. deposition

The phase change process in which solids gets converted to gases is sublimation.

Explanation:

For the given options:

Option a:  Condensation

It is a type of process in which phase change occurs from gaseous state to liquid state at constant temperature.

Option b:  Melting

It is a type of process in which phase change occurs from solid state to liquid state at constant temperature.

Option c:  Sublimation

It is a type of process in which phase change occurs from solid state to gaseous state without passing through the liquid state at constant temperature.

Option d:  Deposition

It is a type of process in which phase change occurs from gaseous state to solid state without passing through the liquid state at constant temperature.

Hence, the phase change process in which solids gets converted to gases is sublimation.