Calculate the energy transferred when 2 kg of ice melts at 0°C. The specific latent heat of fusion for ice is 334,000 J/kg (Changes of state and specific latent heat)

The correct answer is 668,000 J.

Evidence lens: Use the data, graph feature, practical observation, or particle behaviour that proves the answer. This question asks: Calculate the energy transferred when 2 kg of ice melts at 0°C. The specific latent heat of fusion for ice is 334,000 J/kg (Changes of state and specific latent heat). The correct response is 668,000 J, because density links mass and volume, so the answer must preserve which quantity is being calculated. In Changes of state and specific latent heat, the marking point should connect directly to calculate energy transferred during melting, freezing, boiling or condensing when mass and specific latent heat are known. 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 393 is distinct because it uses this exact question context and the evidence lens rather than a generic particle-model sentence.