Though you add heat, the temperature of boiling water remains constant because ...

Question

it takes energy to break hydrogen bonds.
it takes energy to circulate water.
water has a constant boiling temperature.
it takes energy to break covalent bonds.
None of the above. The temperature rises during boiling.

Answer 1

The correct answer is: it takes energy to break hydrogen bonds.

When water reaches its boiling point, adding heat does not increase its temperature; instead, the energy is used to break the hydrogen bonds between water molecules. This process allows the water to change from a liquid state to a gaseous state (steam) while maintaining a constant temperature.