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A heat pump receives energy by heat transfer from the outside air at 0 C and discharges energy by heat transfer to a dwelling at 20 C. Is this in violation of the Clausius statement of the second law of thermodynamics? Explain.

Air as an ideal gas expands isothermally at 20 C from a volume of 1 m3 to 2 m3 . During this process there is heat transfer to the air from the surrounding atmosphere, modeled as a thermal reservoir, and the air does work. Evaluate the work and heat transfer for the process, in kJ/kg. Is this process in violation of the second law of thermodynamics? Explain.