A refrigerator is connected to a generator powered by a fuel with a calorific value of 35000 kJ/kg and a density of 0.85 g/cm3 . The inside temperature of the refrigerator is 0°C, and the outside temperature is 20°C. a. How much work is required to freeze 500 g of water? ΔfreezingH° = 6.02 kJ mol– 1 ) b. How much internal energy change occurs during the process? c. Since the generator consumes 5 L of fuel per hour, calculate the thermal efficiency of this engine.

A refrigerator is connected to a generator powered by a fuel with a calorific value of 35000 kJ/kg and a density of 0.85 g/cm3 . The inside temperature of the refrigerator is 0°C, and the outside temperature is 20°C. a. How much work is required to freeze 500 g of water? ΔfreezingH° = 6.02 kJ mol– 1 ) b. How much internal energy change occurs during the process? c. Since the generator consumes 5 L of fuel per hour, calculate the thermal efficiency of this engine.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter2: Matter And Energy

Section: Chapter Questions

Problem 27RQ: How many Btu/h would be produced in a 12-kW electricheater?

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