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Problem No: $2$ An insulated rigid tank is divided into two equal parts by a partition. One part of the tank contains $0\mathrm{.}5$ mole of air at $500$ kPa and $60^($@$)$C while the other part is evacuated. The partition is removed, and the air expands to fill the entire tank $($The process is not reversible$).$ Determine the entropy change of the air and S$\_($gen$)$ during this process