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Phase change is the process where a substance changes from one state of matter to another. For example, when water boils, it transitions from a liquid to a gas - this gas is what we call steam. When a phase change occurs, it is crucial to understand that the temperature of the substance remains constant. This happens because the energy supplied is used exclusively to change the state, not the temperature.

During the boiling of water, the phase change takes place at a fixed temperature known as the boiling point. At this point, water molecules gain enough energy to overcome intermolecular forces binding them in a liquid state, allowing them to escape into a gaseous form. This fascinating phenomenon shows how energy dynamics work during phase transitions.

The boiling point is a distinct temperature where the pressure of the liquid matches the pressure of the surrounding atmosphere, allowing bubbles of vapor to form within the liquid. For water, this temperature is 100°C or 212°F at sea level.

What makes boiling unique is that the temperature of the liquid does not rise beyond the boiling point. Instead of rising, any additional energy supplied is directed towards breaking the bonds between molecules in the liquid. For water to fully convert from a liquid to a gas, this binding energy needs to be overcome. Hence, the boiling point remains a crucial factor to understand when studying phase changes and heat energy dynamics.

Heat transfer is the process by which thermal energy moves from one body or substance to another. It occurs due to temperature differences. In the context of boiling water, heat is transferred to water molecules, increasing their energy.

However, once water reaches its boiling point, something interesting occurs. Instead of causing a rise in temperature, the heat is used to facilitate the transition from liquid to steam. This energy consumption is known as latent heat, specifically the latent heat of vaporization.\[\[ Q = mL \]\] where \( Q \) is the heat energy, \( m \) is the mass of the substance, and \( L \) is the latent heat of vaporization.

In summary, though heat transfer continues actively during boiling, all the energy goes into changing the phase of the water, not its temperature. This neat partition of energy explains why the boiling temperature stays steady until all water has vaporized.