<prompt> Sublimation is the conversion of a:Solid directly to gasGas to liquid and then to solidGas directly to liquidSolid to liquid and then to gas  <response>: It is possible for some solids to change directly to a vapor by a process called sublimation as seen in dry ice; this, however, has no practical importance as far as dental materials are concerned.Sublimation is the conversion of a solid directly to gas.Reference: PHILLIPS SCIENCE OF DENTAL MATERIALS, 12th ed page no 18 