To summarize electrolysis, consider the following points
Cations of less active metals are reduced to
the metal; cations of more active metals are NOT
That is, most transition metal cations
are more readily reduced than water; water is
more readily reduced than main group metals.
Anions that are oxidized because of
overvoltage of O
formation include the halides
Anions that are NOT oxidized include F
common oxoanions such as SO
, and PO
because the central nonmetal in the oxoanions is already
in its highest oxidation state.