Why is hydrogen in chemical equations written as H2 when the element itself is just H ?
E -LRB- H + / H2 -RRB- is exactly equal to E -LRB- H2O/H2 -RRB- when concentration of H + is same in both the cases but Eo -LRB- H + / H2 -RRB- is not equal to Eo -LRB- H2O/H2 -RRB- . What does this statement mean ?