So for the voltaic cell with the overall reaction, we have our standard cell potential as being equal to 1.10 volts. So our overall cell potential is this value here, it says, given that the standard reduction potential of zinc to ion to zinc solid is negative 0.6762 volts, calculate the standard reduction potential four copper two plus plus two electrons giving us copper solid. Alright, so in this question we have our redox reaction, zinc is going from its neutral natural state where oxidation number is equal to zero to its charge state. Remember for an eye on its charge equals its oxidation number. So here it's plus two, it goes from an oxidation number of zero to an oxidation number of plus two. Since its oxidation number has increased its undergone oxidation and because it represents oxidation, it's going to be the anodes. Then we're going to say within this equation we have copper two plus. So oxidation numbers plus two and it goes to zero. Right? So it's being reduced. Therefore it represents the cathode. Where reduction occurs here, we assume our concentrations have gone to unity, so they're equal to one Moeller. Therefore my standard cell potential equals cathode minus anodes. So my standard cell potential is 1.10 volts. We don't know what the potential of our cathode is. That's what we're looking for, minus a minus 0.762 volts. So remember minus of a minus really means positive. So now subtract .762V from both sides. So the potential here for my cathode would be equal to .338V. So that would be our final answer. So just remember for questions like this, it's important to be able to look at the redox reaction and determined from that what's been oxidized and therefore represents the anodes and what's been reduced and therefore represents the cathode. Once you've figured that out, just remember to fall back on the equation fill in the given values and sulfur, the missing variable, which in this case was just the potential of my cathode.
