Physical states are different in compounds if we have a change of temperature or pressure, and in certain temperatures we can see a compound undergo a physical change, going from solid to liquid or gas, and the reverse is also possible, as we will see now:
If liquid is turning into solid, then we have a freezing situation
Liquid to solid will be known as melting
Gas to liquid will be known as condensing
Liquid to gas will be known as vaporizing