A gas become a liquid after cooling to the adequate temperature - the condensation point.
If a liquid was to boil to change state, it would be changing from a liquid to a gas, and would be said to be boiling.
sublimate
liquid to gas is called evaporation and gas to liquid is condensation
In order for a liquid to become a gas, the particles in the liquid have to heat up enough to separate and further themselves out from each other. Bobette la Baleine : That's what I said in a shorter way.
I'm going to assume your question is asking for what said transition is called. The phase change of a liquid to a gas is vaporization. Vaporization can be broken down into evaporation and boiling.
Solid
General classes of colloids are: gas in liquid, gas in solid, liquid in gas, liquid in liquid, liquid in solid, solid in gas, solid in liquid, solid in solid.
evaporation solid to liquid - melting liquid to gas - evaporation gas to liquid - condensation liquid to solid - freezing solid to gas and gas to solid - sublimation
There are three states of matter that exist on earth: solids, liquids and gasses. When matter goes from a solid state to a liquid, that matter is said to have melted. From liquid to gas it is called vaporizing. From a gas to a liquid is condensation and from liquid to solid is freezing.
At the boiling point a liquid is transformed in a gas; it is a change of phase, a physical process.
liquid molecules forming a gas and gas molecule forming a liquid are equal in number
evaporation solid to liquid - melting liquid to gas - evaporation gas to liquid - condensation liquid to solid - freezing solid to gas and gas to solid - sublimation