10 mol of an ideal gas (gamma= 1.5)expands adiabatically from (400K,10L) to 20 L along following paths. Path A : Reversible Path B : One step expansion. Path C : Two step expansion. Path D : Free expansion Which is/are correct statement(s) ?

10 mol of an ideal gas (gamma= 1.5)expands adiabatically from (400K,10

1.	10 mol of an ideal gas (gamma= 1.5)expands adiabatically from (400K,10L) to 20 L along following paths. Path A : Reversible Path B : One step expansion. Path C : Two step expansion. Path D : Free expansion Which is/are correct statement(s) ?
Answer» Final temperature attained along path B is maximum. Total change in entropy along path-D is 10R In2. Change in entropy of gas along path A is zero. Final temperature attained along path D is 400 K. Solution :`DeltaU=q+w=o +w=w` `n_(Cvm)(T_(2)-T_(1))=w` `T_(2)=T_(1)+(w)/(n_(Cvm))` `w=-x` `T_(2)=T_(1)+(x)/(n_(Cvm))` x is minimum along path B. So `T_(2)` is maximum. Pathd-D `DeltaS_("total")=DeltaS_("SYSTEM")+DeltaS_("SURROUNDING")` `Delta_("total")=nC_(vm)ln .(T_(2))/(T_(1))+nRln.(V_(2))/(V_(1))+O` `T_(2)=T_(1)` (for free expansion) `DeltaS_("total")=10Rln2` Path A `DeltaS_("gas")=0` for reversible adiabatic process. Path-D `T_(2)=T_(1)+(w)/(n_(Cvm))w=0` `T_(2)=T_(1)=400K`