When a substance is undergoing a phase change, turning from a solid to a liquid, or from a gas to a liquid, which two facts are true.

A
Chemical bonds are broken when changing one phase to another phase

B
The reaction that takes place is a physical change opposed to a chemical change.

C
A phase change occurs relatively easy because no energy is involved in the process.

D
The reaction when a substance undergoes a phase change does not cause molecules to break apart.