Enthalpy of vaporization of benzene is +35.3kJ mol-1 at its boiling point, 80° C . The entropy change in the transition of the vapour to liquid at its boiling point [in JK-1mol-1 ]is

Question

Enthalpy of vaporization of benzene is +35.3kJ mol-1 at its boiling point, 80° C . The entropy change in the transition of the vapour to liquid at its boiling point [in JK-1mol-1 ]is (A)  - 441  (B)  -100  (C)  +441  (D)  +100

Tardigrade Admin · Accepted Answer

Entropy change in the transition of the vapour to liquid, Δ condS=(Δ Hcond/Tb)=(-35.5× 103J mol-1/(80+273)K) =-100JK-1mol-1

Q. Enthalpy of vaporization of benzene is $+ 35.3 k J$ $m o l^{- 1}$ at its boiling point, $80^{\circ} C$ . The entropy change in the transition of the vapour to liquid at its boiling point [in $J K^{- 1} m o l^{- 1}$ ]is

$- 441$

$- 100$

$+ 441$

$+ 100$

Entropy change in the transition of the vapour to liquid, $Δ_{co n d} S = \frac{Δ H _{co n d}}{T _{b}} = \frac{- 35.5 \times 10 ^{3} J m o l ^{- 1}}{( 80 + 273 ) K}$ $= - 100 J K^{- 1} m o l^{- 1}$

Q. Enthalpy of vaporization of benzene is +35.3kJ mol−1 at its boiling point, 80∘C . The entropy change in the transition of the vapour to liquid at its boiling point [in JK−1mol−1 ]is

−441

−100

+441

+100