Coordination Compounds - Result Question 47
####53. Which among the following is a paramagnetic complex?
[NEET Kar. 2013]
(a) $[Mo(CO)_6]$
(b) $[Co(NH_3)_6]^{3+}$
(c) $[Pt(en) Cl_2]$
(d) $[CoBr_4]^{2-}$
(At. No. of $Mo=42, Pt=78$ )
Show Answer
Solution:
- (d) $Co^{2+} \Rightarrow[Ar] 3 d^{7} 4 s^{0}$, here, $Br^{-}$is a weak field ligand so will not cause pairing of $d$-electrons in $Co^{2+}$.
$\therefore[CoBr_4]^{2-}$ will exhibit paramagnetic behaviour due to unpaired electrons.
