Question

If an ice cube melts at 0oC but water also freezes at 0oC, what is the difference between melting and freezing in terms of (a) the energy involved in the phase changes and (b) particles of the substances during the phase changes?

Answer 1

Whether the net heat transfer is in or out. The phase change solid/liquid involves the assembly of H2O molecules into a crystal structure vs a mostly random assembly of H2O molecules.