CHEMISTRY COMMUNITY

How do you determine n (number of moles of electrons) by simply looking at a redox rxn to us the equation G=-nFE? Or do you have to write out and balance the whole thing? Thanks!

I usually did balance out the half reactions in order to determine the n. If there are any other ways, I would be glad to know too!

I usually balance out the half reactions. If the redox rxn that is given is balanced, you only need to balance one of the half reactions to see how many moles of electrons you need.

I also usually balance the half reactions in order to see how many electrons need to be exchanged in order for them to cancel when you add the two half reactions together.

The only way of knowing n is by balancing the half reactions - so, that the electrons lost and gained tally.

It helps to balance out the half reactions to see how many moles of electrons are gained/lost.

Like stated above, if the redox reaction that is given is already balanced, you can just look at either half-reaction to see how many electrons cancel out since everything is already properly balanced.