Answer:
1.Freezing of water
Water molecules move toward each other to form hydrogen bonds.
Molecules arrange in a hexagonal crystal structure.
Removal of heat energy stabilizes the phase.
2.Melting of water
Water molecules move away from each other to break hydrogen bonds.
Addition of heat energy stabilizes the phase.
3.Both freezing and melting of water
At 0 ?C, molecules enter the phase.
At 0 ?C, molecules are lost from the phase.