A complex of a certain metal ion has a magnetic moment of `4.90BM` Another complex of the same metal ion in the same oxidation state has zero magnetic moment The central metal ion could be which of the following (a) `Cr^(3+)` ,(b) `Mn^(3+)` (c ) `Fe^(2+)` (d) `Co^(2+)`
(ii) Refer to the question above if a metal ion has complex ion and with magnetic moments `4.90` and `2.8BM` which one of these is the central metal ion
(a) `Cr^(3+)` (b) `Mn^(3+)` , (c ) `Fe^(2+)` (d) `Co^(2+)` .