Chemistry - Thermodynamics - I Question with Solution | TestHub
Statement 1: The magnitude of work done by an ideal gas in reversible adiabatic expansion from the same initial volume to the same final pressure and volume is greater than that in reversible isothermal process.
Statement 2: If an ideal gas is expanded reversibly from the same initial volume to the same final pressure and volume, then the initial pressure is greater in adiabatic process than in isothermal process.
Options:
Answer:
Solution:
Same final state (P2,V2) means the same final temperature T2=P2V2/nR. The isothermal path starts at T2; an adiabatic expansion cools the gas, so it must start hotter, T1ad>T2. With the same V1, P1ad=nRT1ad/V1>P1iso: II is correct. Both curves end at P2; the adiabatic curve P=P2(V2/V)γ lies above the isotherm P=P2(V2/V) for V<V2 (as γ>1), so the area under it is larger: I is correct and follows from II. Answer (a).
