* Breaking Bonds: Water molecules (H₂O) are held together by hydrogen bonds. These bonds are relatively weak compared to the covalent bonds within the molecule itself. When you heat water, you provide energy to these molecules. This energy causes the molecules to vibrate faster.

* Increased Spacing: As the molecules vibrate faster, they push against each other more strongly. This increased kinetic energy overcomes the attractive forces of the hydrogen bonds, causing the molecules to break free from each other and move further apart.

* Phase Change: The increased spacing between molecules is what causes the phase change from liquid to gas (steam). In the gas phase, the molecules are much farther apart and move much more freely.

* Atoms Remain: Importantly, the atoms themselves do not change. The hydrogen and oxygen atoms that make up the water molecules remain intact. They simply become separated from each other as the bonds between water molecules break.

In summary: Boiling water doesn't destroy the atoms, it just changes how they are arranged and how they interact with each other.