I believe its sublimation. An example of it could be like dry ice.
Hope that helps!
Answer : The change of phase from a solid to a gas is called sublimation.
Explanation :
Melting or fusion : It is a type of process in which the phase changes from solid state to liquid state at constant temperature.
Freezing : It is a type of process in which the phase changes from liquid state to solid state at constant temperature.
Evaporation : It is a type of process in which the phase changes from liquid state to gaseous state at constant temperature.
Condensation : It is a type of process in which the phase changes from gaseous state to liquid state at constant temperature.
Sublimation : It is a type of process in which the phase changes from solid state to gaseous state without passing through the liquid state at constant temperature.
Deposition : It is a type of process in which the phase changes from gaseous state to solid state without passing through the liquid state at constant temperature.
Hence, the change of phase from a solid to a gas is called sublimation.
