What occurs during a phase change?

During a phase change, energy is absorbed or released without a temperature change, which is fundamental to understanding how substances transition between states such as solid, liquid, and gas. Phase changes occur at specific temperature ranges and involve changes in the arrangement and movement of particles in a substance.

For example, during melting, a solid absorbs energy in the form of heat, which allows the particles to overcome their rigid structure and move more freely, transitioning into a liquid state. However, the temperature remains constant during this process until all the solid has melted. Similarly, during freezing, a liquid releases energy, allowing particles to come closer together and form a solid without a change in temperature until the process is completed.

This characteristic defines phase changes and highlights why options associated with temperature changes or reactions do not apply. In a phase change, the focus is specifically on the energy transformation while the temperature stabilizes temporarily. Thus, option B accurately captures the essence of what occurs during a phase change.