Which of these phase changes does not involve changing a liquid into a gas?
vaporization
sublimation
boiling
evaporation

The answer is sublimation.

Sublimation is the chemical process whereby a solid turns into a gas without first becoming a liquid.

The word sublimation comes from the Latin word sublimare which means "raised to a higher status."

Examples of sublimation include surface layer of snow and ice turning into steam or fog without melting and  dry ice which is the solid form of carbon dioxide  which also undergoes sublimation.

The low temperature and sublimation makes dry ice an effective coolant or cooling agent . One of its main advantages is that it has a lower temperature than water ice and also does not leave any residue.