3. For a stable phase at constant pressure and temperature, the fugacity of each component in a binary system __________ as its mole fraction increases.
5. The co-efficient of performance (COP) of a refrigerating system, which is its index of performance, is defined as the ratio of useful refrigeration to the net work. The units of __________ and COP are the same.
Correct Answer: Under reversible conditions, the adiabatic work is less than isothermal work.
10. A refrigeration cycle is a reversed heat engine. Which of the following has the maximum value of the co-efficient of performance (COP) for a given refrigeration effect?
Options
A. Vapor compression cycle using expansion valve.
B. Air refrigeration cycle.
C. Vapor compression cycle using expansion engine.