2/22 in class example E(nought)

[Kathryn 1F]

In class we had E(nought)=0.77V for Fe3+ + e- = Fe2+
When we multiplied the eqn by 2 to get 2Fe3+ + 2e- = 2Fe2+, we kept E(nought)=0.77V.

Why is this? Why didn't we multiply .77 by 2?

[Jonathan Pai 2I]

E is an intensive property, so it doesn't matter how many reactions or the ratio's of it. But reversing does affect if it is positive or negative.

[pamcoronel1H]

I'm not completely sure on this, but I think it's because E(nought) by definition is the STANDARD reduction potential that gives the voltage difference of two electrodes. Since it gives you the voltage difference, this makes E(nought) an intensive property and therefore doesn't change no matter how many stoichiometric coefficents you add.