How much heat is needed to warm 0.5 kg of water by 10 °C? (specific heat capacity of water = 4200 J/(kg °C))
Answer and explanation
Correct answer: D. 21000 J
- Step 1: Q = mcΔT. Step 2. Q = 0.5 × 4200 × 10 = 21000 J. Answer: 21000 J. Why not the others: 42000 J is what you get if you forget the mass. 5 J is what you get if you forget the specific heat capacity. 21 J is what you get if you convert to kilojoules without changing the unit.
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