One mole of an ideal gas is compressed isothermally but irreversibly at 7 7 ∘ C from 2 bar to 4 bar in a cylinderpiston device. The work required is 20% greater than the work of reversible isothermal

Question

One mole of an ideal gas is compressed isothermally but irreversibly at $7 7^{\circ} C$ from 2 bar to 4 bar in a cylinderpiston device. The work required is $20%$ greater than the work of reversible isothermal compression. The heat transferred from the gas during compression flows to a heat reservoir at $2 7^{\circ} C$ . Calculate the $Δ S_{total}$ in $JK^{- 1}$ .

Given : R = 8 JK^-1mol^-1 , ℓn2 = 0.7

TestHub · Accepted Answer

Δ S = nR ln P 2 ​ P 1 ​ ​ = 1 × 8 × ln 4 2 ​ = − 5.6 JK − 1 Δ S surr ​ = T − Q sys ​ ​ = T W irr ​ ​ = 300 1.2 × W rev ​ ​ = 300 1.2 × 350 × 5.6 ​ = 7.84 JK − 1 Therefore, Δ S total ​ = 7.84 − 5.6 = 2.24 JK − 1

Chemistry - Thermodynamics - II Question with Solution | TestHub

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