8.17 For and
systems, the
values for some metals are as follows:
Use this data to comment upon:
(i) the stability of in acid solution as compared to that of
or
The value of
is higher than that of
but less than that of
. So, the reduction of ferric ion (
) to ferrous ion(
) is easier than
but as easy as
. Hence, ferric ion is more stable than manganese ion(
), but less stable than chromium ion(
).
The order of relative stabilities of different ions is: