OCR Advanced GCE in Chemistry/Electrode potentials/What?

There could be a question that will ask if a reaction is feasible in the opposite direction to the way that you would expect it to go from the E^O values. For this, all you have to do is show the calculation in the same way as usual but make the E^O value negative. This shows that the reaction is going in the other way. Because the reaction is not feasible, the value will be negative.