What is the maximum theoretical efficiency possible for a heat engine operating between a reservoir in which ice and water coexist,and a reservoir in which water and steam coexist? The pressure is constant at 1.0 atmosphere for both reservoirs.
A) 27%
B) 45%
C) 73%
D) 17%

Question

Quizplus · Accepted Answer

The maximum theoretical efficiency of a heat engine is given by the Carnot efficiency, which is calculated using the temperatures of the hot and cold reservoirs (Th and Tc, respectively) in Kelvin. The temperature at which ice and water coexist (the melting point of ice) is 0°C or 273K, and the temperature at which water and steam coexist (the boiling point of water) is 100°C or 373K under 1.0 atmosphere pressure. The Carnot efficiency is given by 1 - (Tc/Th), so the efficiency is 1 - (273/373) = 0.268, or 26.8%, which rounds to approximately 27%.

What Is the Maximum Theoretical Efficiency Possible for a Heat