Explain how heating a substance affects the energy stored within the system.

Heating a substance increases the energy stored within the system by raising the kinetic energy of its particles. As the temperature rises, the particles move faster, which increases their overall energy.

Application lens: Apply the rule to the specific sample or situation instead of reciting a broad fact. This question asks: Explain how heating a substance affects the energy stored within the system. The correct response is Heating a substance increases the energy stored within the system by raising the kinetic energy of its particles. As the temperature rises, the particles move faster, which increases their overall energy., because the particle model explains the observable property using particles. In Internal energy, the marking point should connect directly to explain that heating changes the energy stored within a system by increasing particle energy. 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 223 is distinct because it uses this exact question context and the application lens rather than a generic particle-model sentence.