Which of the following electrodes will act as anodes, which are connected to Standard Hydrogen Electrode?

1.  Al/Al3+ E=-1.66

2.  Fe/Fe2+ E=-0.44

3.  Cu/Cu2+ E=+0.34

4.  F2(g)/2F-(aq) E=02.87

(a, b)
All electrodes which have negative electrode potential are stronger reducing agents than H2 gas and hence acts as anodes when connected to standard hydrogen electrodes. Thus, Al3+/Al (E=1.66 V) and Fe2+/Fe (E=0.44V) act as the anode.