Problem $09\mathrm{.}042-$ Piston air compression

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A piston$$cylinder device initially contains $3\mathrm{.}00$ L of air at $100$ kPa and $25$C$.$ Air is now compressed to a final state of $600$ kPa and $150$C$.$ The useful work input is $1\mathrm{.}2$ kJ$.$ Assume the surroundings are at $100$ kPa and $25$C$.$

Problem $09\mathrm{.}042.$a $-$ Exergies of piston air compression

Determine the exergy of the air at the initial and the final states. The gas constant of air is R$=0\mathrm{.}287$kPa$$m$3/$kg$$K$.$R$=0\mathrm{.}287$kPa$$m$3/$kg$$K$.$ Use the table containing the ideal$-$gas specific heats of various common gases. $($Round the final answer to three decimal places.$)$

The exergy of the air at the initial state is kJ$.$

The exergy of the air at the final state is kJ$.$ Determine the minimum work that must be supplied to accomplish this compression process. $($Round the final answer to three decimal places.$)$

The minimum work that must be supplied is kJ$.$ Determine the second$-$law efficiency of this process.

The second$-$law efficiency of this process is $\%.$