What characterizes the state of matter at the boiling point?

The boiling point is characterized by the transition of molecules from the liquid phase to the gas phase due to increased energy. At this temperature, the energy absorbed by the liquid molecules overcomes the intermolecular forces holding them together in the liquid state. As the temperature increases, the molecules gain kinetic energy, and when they reach the boiling point, they have sufficient energy to break free from the liquid's surface and enter the gas phase. This process is known as vaporization.

At the boiling point, the energy input leads to an increase in the molecular motion, allowing the liquid to change into vapor. This is a critical phase change that occurs at a specific temperature characteristic for each substance, known as its boiling point.