Arrange following complex ions in increasing order of crystal field splitting energy (Δ0) [CrCl6]3-, [Cr(CN)6]3-, [Cr(NH3)6]3+

Question

Arrange following complex ions in increasing order of crystal field splitting energy (Δ0) [CrCl6]3-, [Cr(CN)6]3-, [Cr(NH3)6]3+ (A) [Cr(NH3)6]3+ < [CrCl6]3- < [Cr(CN)6]3+ (B) [CrCl6]3- < [Cr(NH3)6]3+ < [Cr(CN)6]3- (C) [CrCl6]3- < [Cr(CN)6]3- < [Cr(NH3)6]3+ (D) [Cr(NH3)6]3+ < [Cr(CN)6]3- < [CrCl6]3-

Tardigrade Admin · Accepted Answer

Cl- is a weak field ligand while CN- is a strong field ligand. Hence, the order of crystal field splitting energy (Δ0) is [CrCl6]3- < [Cr(NH3)6]3+ < [Cr(CN)6]3-

Q. Arrange following complex ions in increasing order of crystal field splitting energy $(Δ_{0})$
$[C r C l_{6}]^{3 -}, [C r (CN)_{6}]^{3 -}, [C r (N H_{3})_{6}]^{3 +}$

$[C r (N H_{3})_{6}]^{3 +} < [C r C l_{6}]^{3 -} < [C r (CN)_{6}]^{3 +}$

$[C r C l_{6}]^{3 -} < [C r (N H_{3})_{6}]^{3 +} < [C r (CN)_{6}]^{3 -}$

$[C r C l_{6}]^{3 -} < [C r (CN)_{6}]^{3 -} < [C r (N H_{3})_{6}]^{3 +}$

$[C r (N H_{3})_{6}]^{3 +} < [C r (CN)_{6}]^{3 -} < [C r C l_{6}]^{3 -}$

$C l^{-}$ is a weak field ligand while $C N^{-}$ is a strong field ligand.
Hence, the order of crystal field splitting energy $(Δ_{0})$ is
$[C r C l_{6}]^{3 -} < [C r (N H_{3})_{6}]^{3 +} < [C r (CN)_{6}]^{3 -}$

Q. Arrange following complex ions in increasing order of crystal field splitting energy (Δ0​) [CrCl6​]3−,[Cr(CN)6​]3−,[Cr(NH3​)6​]3+

[Cr(NH3​)6​]3+<[CrCl6​]3−<[Cr(CN)6​]3+

[CrCl6​]3−<[Cr(NH3​)6​]3+<[Cr(CN)6​]3−

[CrCl6​]3−<[Cr(CN)6​]3−<[Cr(NH3​)6​]3+

[Cr(NH3​)6​]3+<[Cr(CN)6​]3−<[CrCl6​]3−