One mole of an ideal gas at 350 K is in a 2 . 0 L vessel of thermally conducting walls, which are in contact with the surroundings. It undergoes isothermal reversible expansion from 2 . 0 L to 3 . 0 L

Question

One mole of an ideal gas at 350 K is in a 2 . 0 L vessel of thermally conducting walls, which are in contact with the surroundings. It undergoes isothermal reversible expansion from 2 . 0 L to 3 . 0 L against a constant pressure of 4 atm . The change in entropy of the surroundings ( ∆ S ) is _____ J K – 1 (Nearest integer) Given: R = 8 . 314 J K - 1 mol - 1 .

TestHub · Accepted Answer

The first law of thermodynamics for isothermal process $Q = - W$

The $W$ for isothermal reversible process is

$W = - n R T \ln \frac{V_{2}}{V_{1}}$

$∆ S = \frac{Q}{T}$

$∆ S_{surrounding} = - n R \ln \frac{V_{2}}{V_{1}}$

$= - 1 \times 8.314 \times 2.303 \times \log \frac{3}{2}$

$= - 3.37 {JK}^{- 1}$

$≃ - 3 {JK}^{- 1}$

The given process is mentioned as isothermal reversible process hence the $∆ S_{surrounding}$ is calculated.

Chemistry - Thermodynamics - II Question with Solution | TestHub

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