Q7(e). Reversible isothermal expansion of an ideal gas
An ideal gas (Vi = 0.05 L and Pi = 8 atm) is subjected to reversible isothermal expansion (Vf = 0.40 L and Pf = 1 atm) at 25 °C. Calculate the work done, ΔU, ΔH and ΔS for this process. Is the heat (q) the same as ΔH in this process? If not, why?
Answer in brief
w = −84.3 J; ΔU = 0; ΔH = 0; ΔS = +0.283 J K⁻¹; no, q = +84.3 J but ΔH = 0 because the pressure is not constant.
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Coversreversible isothermal expansionwork doneinternal energyenthalpyentropy changefirst law of thermodynamics
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