Why does temperature remain constant during a change of state?

The correct answer is Energy is used to change particle potential energy rather than average kinetic energy.

Evidence lens: Use the data, graph feature, practical observation, or particle behaviour that proves the answer. This question asks: Why does temperature remain constant during a change of state. The correct response is Energy is used to change particle potential energy rather than average kinetic energy, because specific heat capacity links energy, mass, material and temperature change. In Temperature changes in a system and specific heat capacity, the marking point should connect directly to apply MS 3b and MS 3c skills when rearranging and calculating with the specific heat capacity equation. If the question includes values, the working must keep the appropriate unit and operation; if it is an explanation, it must name the relevant particle behaviour or energy change. This item belongs to Internal energy and energy transfers, so avoid answers that switch to a different quantity, confuse heat with temperature, or describe gas pressure without collisions when collisions are the reason. Checkpoint 357 is distinct because it uses this exact question context and the evidence lens rather than a generic particle-model sentence.