Final Winter 2013

[camrynpatterson3C]

Question 4 about the droplets assumes that the number of moles is 4. How do we know this??

[Christiana2D]

The number 4 is the moles of electrons being transferred in the reaction. This number can be determined by looking at the number of electrons present in the half reactions, or by looking at the oxidation numbers of the reactants and products. For the products the Iron has a plus 4 charge and the OH minus combined has a -4 charge.

[ZoeHahn1J]

We know n=4 because that's the number of moles of electrons transferred when Fe is oxidized and O2 is reduced - split the reaction into two half reactions to check.

[Jason Muljadi 2C]

Can't you also tell because there is (OH)₂ meaning that there will be 4e^-'s due to the charge of O always being 2- and there's 2 of them?