Question

what type of bond or attraction is broken when heat is added to the liquid?
the nonpolar covalent bond within the water molecule
the polar covalent bonds within the water molecule
the hydrogen bond between different water molecules

Explanation:

When heat is added to liquid water (a common liquid reference here), the liquid changes state (e.g., evaporates) by overcoming intermolecular attractions, not breaking the strong covalent bonds within individual water molecules. Water molecules have polar covalent bonds internally, which require far more energy to break than typical heating of a liquid provides. Hydrogen bonds are the weaker intermolecular attractions between separate water molecules that are disrupted when liquid water is heated (for boiling or evaporation).

Answer:

the hydrogen bond between different water molecules