Is delta enthalpy zero for

Is delta enthalpy zero for....

Is delta H, for an isothermal process in which a gas expands?
delta H=delta U+work done,correct?
delta U is 0,but work done = nCln(V2/V1).
So,delta H is not equal to 0.But my book says so.
 

Ygggdrasil

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Re: Is delta enthalpy zero for....

delta H=delta U+work done,correct?
.
No. deltaH = deltaU + delta(PV). Work done is p delta(V) (under conditions of constant pressure).

For an ideal gas delta(PV) = R delta(nT). As long as the number of gas molecules in the system (n) and the temperature (T) remain constant, delta(PV) = 0.
 

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