The type of process that occurs when solidified wax is converted to liquid wax is ENDOTHERMIC.
In chemistry, there are two basic types of reaction based on absorption or release of energy, these are exothermic and endothermic reaction. A reaction is said to be exothermic if it releases energy into the environment. An endothermic reaction is one which absorbs energy from the external environment. In order for solid wax to melt and become liquid, heat has to be applied to the solid wax, the heat is the thermal energy, which the reaction absorb from the environment.