ΔH=nCpΔT=0,∴ΔT=0
∴ Pext = defined
so process is irreversible.
ΔS=nRln (Vf/Vi)≥0
An ideal gas undergoes isothermal expansion at constant pressure. During the process:
Held on 9 Apr 2017 · Verified 6 Jul 2026.
Enthalpy remains constant but entropy increases
Enthalpy decreases but entropy increases
Enthalpy increases but entropy decreases
Both enthalpy and entropy remain constant
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