Question

1 mole of an ideal gas is allowed to expand isothermally at `27^(@)`C till its volume is tripled . If the expansion iscarried out reversibly then the `DeltaS_("universe")` will be?

Answer 1

In isothermal revbersible process.
`DeltaS=(q_("rev"))/(T)`
`q=-w=2.303 RT "log" (V_(2))/(V_(1)) = 2740.6 J//"mole"`
`DeltaS_("surr")= (q_("rev"))/(T) = (2740.6)/(300) =9.135 J//K "mole"`
`DeltaS_("surr") = -DeltaS_("system") =- 9.135 JK^(-1) "mole"^(-1)`
`DeltaS_("universe") = 0`