A 0.50 kg block of ice at 0 °C is heated until it becomes water at 0 °C. If the specific latent heat of fusion of water is 3.34 × 10⁵ J kg⁻¹, how much energy is transferred during the phase change (Changes of state and specific latent heat)

The correct answer is 1.67 × 10⁶ J.

Unit lens: Check the units before giving the final statement so the physics quantity is not swapped. This question asks: A 0.50 kg block of ice at 0 °C is heated until it becomes water at 0 °C. If the specific latent heat of fusion of water is 3.34 × 10⁵ J kg⁻¹, how much energy is transferred during the phase change (Changes of state and specific latent heat). The correct response is 1.67 × 10⁶ J, because changes of state are explained by particle energy and arrangement. In Changes of state and specific latent heat, the marking point should connect directly to explain that energy transferred during a change of state changes particle potential energy rather than average kinetic 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 421 is distinct because it uses this exact question context and the unit lens rather than a generic particle-model sentence.