A galvanic (voltaic) cell consists of an electrode composed of magnesium in a 1.0 M magnesium ion solution and another electrode composed of copper in a 1.0 M copper(I) ion solution, connected by a salt bridge. Calculate the standard potential (in V) for this cell at 25ºC. Standard reduction potentials can be found here:
Checking the half potential table, Mg appears to be a stronger reducing agent (more negative) than Cu so Cu gets reduced from +1 to 0.
Recall that "Loss of electrons is Oxidation (LEO)" and oxidation occurs at the anode, on the other hand "Gain of electrons is Reduction (GER)" and the electrode is cathode.
Setting up the Ecell equation: