Answer:
The molecular structure will remain the same.
Step-by-step explanation:
When water is heated, the heat supplied breaks down the intermolecular interactions (Hydrogen bondings) between the water molecules. This results in conversion of liquid state to gas state and water vapors evaporate.
While the molecular structure keeps intact. It is not changed. Hence, when the heat is removed the vapors of water condense back to liquid state and releases the heat which was absorbed during vaporization.