Calculate the energy transferred when 2 kg of water is heated from 20°C to 80°C. The specific heat capacity of water is 4,200 J/kg°C (Temperature changes in a system and specific heat capacity)

The correct answer is 504,000 J.

Particle lens: Describe arrangement, motion, spacing, collisions, or energy changes only when they are relevant here. This question asks: Calculate the energy transferred when 2 kg of water is heated from 20°C to 80°C. The specific heat capacity of water is 4,200 J/kg°C (Temperature changes in a system and specific heat capacity). The correct response is 504,000 J, because specific heat capacity links energy, mass, material and temperature change. In Temperature changes in a system and specific heat capacity, the marking point should connect directly to rearrange the specific heat capacity equation for any required variable. 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 324 is distinct because it uses this exact question context and the particle lens rather than a generic particle-model sentence.