Which bivalent ion of first transition series show the highest paramagnetism?

Explanation

(a) In elemental form:
`3d` series: `Cr (Z = 24) rArr 3d^(5) 4s^(1),n = 6, mu = sqrt(6+(6+2))`
`= sqrt(48) BM`
`4d` series: `Mo(Z=42) rArr 4d^(5) 5s^(1),n=6, mu = sqrt(48) BM`
`5d` series: `W(Z=74) rArr 5d^(4) 4s^(2),n=4, mu = sqrt(24) BM`
But `Re` has the highest number of unpaired `e^(-)`, as shown:
`Re(Z=75) rArr 5d^(5) 6s^(2),n = 5, sqrt(35) BM`
(b) `In + 1` oxidation state:
`3d` series: `Mn(Z=25) rArr3d^(5) 4s^(2), Mn^(1+) = 3d^(5) 4s^(1), n=6, mu = sqrt(48) BM`
`4d` series: `Te(Z = 43) rArr 4d^(5) 5s^(2), Te^(1+) = 4d^(5) 5s^(1), n=6, mu = sqrt(48) BM`
`5d` series: `Re(Z=75) rArr 5d^(5) 6s^(2), Re^(1+)=5d^(5) 6s^(-),n=6, mu=sqrt(48) BM`
(c ) `In+2` oxidation state:
`3d` series: `Mn(Z=25) rArr 3d^(5) 4s^(2), Mn^(2+) = 3d^(5), 4s^(0),n=5, mu = sqrt(35) BM`
`4d` series: `Te(Z=43) rArr 4d^(5) 6s^(2), Te^(2+)=4d^(5) 5s^(0),n=5, mu = sqrt(35) BM`
`5d` series: `Re(z=75) rArr 5d^(5) 6s^(2), Re^(2+)=5d^(5) 6s^(0),n=5, mu = sqrt(35) BM`
(d) `In+3` oxidation state:
`3d` series: `Fe(Z=26) rArr 3d^(6) 4s^(2), Fe^(3+)=3d^(5) 4s^(0),n=5, mu = sqrt(35) BM`
`4d` series: `Ru(Z=44) rArr 4d^(7) 5s^(1)` (exxeption electronic configuration).
`5d` series: `Os (Z=76) rArr 5d^(6) 7s^(2), Os^(3+) = 5d^(5) 7s^(0), n=5, mu = sqrt(35) BM`
Note:
(i) From the abov calculation it is clear that in the elemental form (zero `OS`), group `6` has the highest `mu`, except `W`, in `5d` series, but it is `Re` of group `7`.
(ii) `In+1 OPS`, group `7` has the highest `mu`.
(iii) `In+2 OS`, again group `7` has the highest `mu`.
(iv) `In+3 OS`, group `8` has the highest `mu`.