Today I was studying Atkins physical chemistry basics and I saw a bit of incoherence.(adsbygoogle = window.adsbygoogle || []).push({});

Δ_{r}G°=Δ_{r}H°-TΔ_{r}S°

Δ_{r}G°=Δ_{f}G°(products) - Δ_{f}G°(substrates)

Δ_{r}G°=nFE°

Data: ............ Δ_{f}H° ........... Δ_{f}G°............ΔS°(J*K*mol^{-1})

H_{2(g)}...............0....................0...................130,684

H^{+}....................0.....................0..................0

2H^{+}_{(aq)}2e^{-}=> H_{2(g)}

Using second and third equation second and third equation I get Δ_{r}G°=0

But using first equation I get Δ_{r}G°=Δ_{r}H°-TΔ_{r}S°=0-298*130,684= -39 kJ/mol

I thought I can't calculate ΔG for half reaction but I must have used it while calculating Cu^{2+}+ e^{-}=> Cu^{+}potential

from Cu^{2+}+ 2e^{-}=> Cu and Cu^{+}+ e^{-}=> Cu potentials.

Can someone explain this to me?

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# Hydrogen electrode incoherence?

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