Concept explainers
(a)
The amount of heat lost to the surroundings.
(a)
Answer to Problem 49P
The amount of heat lost to the surroundings is
Explanation of Solution
Express the final volume of the air.
Here, initial volume of air is
Express the mass of air in the large tank.
Here, initial pressure is
Express the pressure of air at the final state.
Here, final temperature of air is
Express the mass of water.
Here, density of water is
Express the amount of heat lost to the surroundings.
Here, specific heat of water is
Conclusion:
Refer Table A-2, “ideal gas specific heats of various gases”, and write the properties of air at room temperature.
Refer Table A-3 (a), “properties of common liquids, solids and foods”, and write the properties of water at room temperature.
Substitute
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Substitute
Substitute
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Hence, the amount of heat lost to the surroundings is
(b)
The exergy destruction during the process.
(b)
Answer to Problem 49P
The exergy destruction during the process is
Explanation of Solution
Express entropy change in water.
Express entropy change in air.
Here, initial pressure of air is
Express net internal energy of water.
Express net internal energy of air.
Express the exergy destruction during the process.
Here, surrounding temperature is
Conclusion:
Substitute
Substitute
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Hence, the exergy destruction during the process is
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Chapter 8 Solutions
THERMODYNAMICS
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