What is the energy transferred when 3 kg of water boils at 100°C? The specific latent heat of vaporisation for water is 2,260,000 J/kg (Changes of state and specific latent heat)

The correct answer is 6,780,000 J.

Practical lens: Link apparatus, readings, and uncertainty to the exact measurement named in the objective. This question asks: What is the energy transferred when 3 kg of water boils at 100°C? The specific latent heat of vaporisation for water is 2,260,000 J/kg (Changes of state and specific latent heat). The correct response is 6,780,000 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 398 is distinct because it uses this exact question context and the practical lens rather than a generic particle-model sentence.