Paramagnetic pairs (s) among the following is (are) .

Options

A. `[BaO_(2),NO_(2)]`
B. `[KO_(2),NO]`
C. `[H_(2)O_(2),NO]`
D. `K_(3)[Fe(CN)_(6)],CuCI_(2)`

Answer

B, D

Explanation

In (b) `O_(2)^(Θ)` (peroxide ion) and` ( :overset(.)N = overset(..)O: )` have one unpaired `e^(-)` paramagnetic
In `K_(3)[Fe(CN)_(6)]` has `Fe^(+3)` as a central metal ion it has five unpaired `e^(-')s` and is paramagnetic ion it has five unpaired `e^(-')s` and is paramagnetic
`Fe (Z =26) implies 3d^(6) 4s^(2), Fe^(+3) implies 3d^(5) 4s^(0)`
`CuCI_(2)` has `Cu^(2+)` ion it has one unpaired `e^(-)` and is paramagnetic
`Cu (Z =29) implies 3d^(10) 4s^(1) Cu^(+2) implies 3d^(9) 4s^(0)` .