How many kilojoules are needed to heat 2 kg of water by 20 °C? (c = 4 kJ/(kg·°C))
Answer and explanation
Correct answer: B. 160 kJ
- Step 1: Q = m c ΔT.
- Step 2: Q = 2 x 4 x 20 = 160 kJ.
Answer
160 kJ.
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