Coordination Compounds Question 10
Question 10 - 29 January - Shift 2
Correct order of spin only magnetic moment of the following complex ions is:
(Given At. No. Fe: 26, Co:27)
(1) $[FeF_6]^{3-}>[CoF_6]^{3-}>[Co(C_2 O_4)_3]^{3-}$
(2) $[Co(C_2 O_4)_3]^{3-}>[CoF_6]^{3-}>[FeF_6]^{3-}$
(3) $[FeF_6]^{3-}>[Co(C_2 O_4)_3]^{3-}>[CoF_6]^{3-}$
(4) $[CoF_6]^{3-}>[FeF_6]^{3-}>[Co(C_2 O_4)_3]^{3-}$
Show Answer
Answer: (1)
Solution:
Formula: CFT, spin magnetic moment
$[FeF_6]^{3-}: Fe^{3+}=3 d^{5} \Delta_0<P$
Number of unpaired $e^{-}=5 \therefore \mu=\sqrt{35} BM$
$[CoF_6]^{3-}: Co^{3+}=3 d^{6}(\Delta_O<P)$
Number of unpaired $e^{-}=4 \therefore \mu=\sqrt{24} BM$
$[Co(C_2 O_4)_3]^{3-}: Co^{3+}=3 d^{6}(\Delta_O>P)$
Number of unpaired $e^{-}=0 \therefore \mu=0 BM$
