Is delta enthalpy zero for.... 1. The problem statement, all variables and given/known data 1 mol of ideal gas expands isothermally at 274 K ,from pressure 1.1 atm to 1 atm.It absorbs 8.314 J of heat.Find free energy change. 2. Relevant equations dG=dH-T dS......1 dS=dq/T dH=dU+Work done Work done=nRTln(P1/P2).....2 3. The attempt at a solution dU=0 dH=Work done dH=whatever u get in 2 dG=whatever u get by substituing values in 1. But my book says dH=0 because the process is adiabatic.Isn't that wrong?