Engineering Board Exam Reviewer · Thermodynamics · medium
One kilogram of water is heated from 300 K to 350 K. What is its change in entropy? (c = 4.187 kJ/kg· K)
- 0.6978 kJ/K
- 0.5981 kJ/K
- 0.6454 kJ/K
- 0.2803 kJ/K
Answer
C. 0.6454 kJ/K
Solution
S = mc (T2/T1) = 4.187 (350/300) = 0.6454 kJ/K.
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