Distinguish between temperature and internal energy in a system.

Temperature is a measure of the average kinetic energy of the particles in a substance, while internal energy is the total energy, including both kinetic and potential energy, of all the particles in the system.

Method lens: First identify the measured quantity, then match the equation or particle idea to the command word. This question asks: Distinguish between temperature and internal energy in a system. The correct response is Temperature is a measure of the average kinetic energy of the particles in a substance, while internal energy is the total energy, including both kinetic and potential energy, of all the particles in the system., 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 224 is distinct because it uses this exact question context and the method lens rather than a generic particle-model sentence.