Enthelpy change of an isothermal process

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sachin123
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what is the enthalpy change of an isothermal process?(Why is it 0?)
 
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delta H=delta U+work done on the system(PV work)
For an isthermal expansion of a gas,delta U is 0.Since the gas expands,W is not zero.Then how can delta H be 0?
 
Δ(pv) isn't pv work, as both pressure and volume are changing. its best to change this to nRΔT. Now its easy to see the because ΔT=0, Δ(pv) is also 0.
 
delta H= nC(p)ΔT where C(p) is molar heat capacity at constant pressure. Since in isothermal process ΔT is zero. Thr4 enthalpy change is zero and the term 'pv' is not work. They are pressure and volume of system respectively...