Q15(b). Entropy along two reversible paths
An ideal gas changes from X(p₁,V₁,T₁) to Z(p₂,V₂,T₁). Route A is isothermal reversible expansion (I). Route B is reversible adiabatic expansion (II) to Y(p₃,V₂,T₂) followed by reversible heating (III) to Z. Calculate the entropy change for each process and each route; compare the two routes.
Answer in brief
ΔSI=nRln (V₂/V₁), ΔS_(II)=0 and ΔS_(III)=nRln (V₂/V₁). Both routes have the same total entropy change.
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CoversEntropy along two reversible pathsEntropy as a state function
All parts of Question 15
- 15(a) Volume contraction on mixing5 marks
- 15(b) Entropy along two reversible paths15 marks