This question was posed by my lecturer on Gibbs free energy, please share your thoughts.

The question goes like this :

delta G = delta U - TdeltaS - PdeltaV

= W_{rev} + PdeltaV

-delta G = -W_{rev} - PdeltaV

-W_{rev} - PdeltaV is reversible work, exclusive of reversible work, also referred as net work.

so -delta G = -W'_{rev} (net work)

We know that gibbs free energy is a state function. But why is that for different pathways from the same initial state to the same final state in free energy, the net work for each pathway can be different when the equation -delta G = -W'_{rev} holds true ?

ie. delta G = NetWork1, delta G = NetWork2, delta G = NetWork3

but NetWork1 is not equal to NetWork2 or NetWork3 but delta G is the same.