you need to refer to your activity series of metals..
the more active metal will lose electrons by oxidation this will be the anode,
the less active metal will gain electrons by reduction and will be the cathode.
essentially: anode is where the current flows in, cathode is where current flows out
hope this is of some aid
Yeah, but you don't exactly have the activity series of metals to refer to in the exam. You do a set of potentials however. So yeah, it's probably better just to check that to determine which one gets oxidised and which one gets reduced.