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NEET CHEMISTRYCoordination CompoundsMedium

Question

The correct statement among the following about [Co(CN)6]3−[Co(CN)_6]^{3-} is :

A

It has no unpaired electrons and will be in a low-spin configuration

B

It has four unpaired electrons and will be in a low-spin configuration

C

It has four unpaired electrons and will be in a high-spin configuration

D

It has no unpaired electrons and will be in a high-spin configuration

Step-by-Step Solution

In the complex [Co(CN)6]3−[Co(CN)_6]^{3-}, the central metal ion is Cobalt (Co) in the +3 oxidation state. The electronic configuration of Co3+Co^{3+} is 3d63d^6. Since the cyanide ion (CN−CN^-) acts as a strong field ligand, the crystal field splitting energy (Δo\Delta_o) is greater than the pairing energy (PP). This leads to the pairing of the six dd-electrons in the lower energy t2gt_{2g} orbitals, resulting in a t2g6eg0t_{2g}^6 e_g^0 configuration. Because all the electrons are paired up, the number of unpaired electrons is zero, making it diamagnetic. It forms an inner-orbital, low-spin complex.

Exam Context & Concepts Covered

This question aligns with the NEET CHEMISTRY syllabus, specifically targeting concepts from Coordination Compounds. Mastering this topic is crucial for scoring well in the upcoming medical entrance examinations. Solving conceptually related problems will help you understand the nuances of these concepts and improve your problem-solving speed.

CHEMISTRYCoordination Compoundscorrectstatementfollowing

More Coordination Compounds Questions

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The complex, $[\text{Pt}(\text{Py})(\text{NH}_3)\text{BrCl}]$ will have how many geometrical isomers?

A.4
B.0
C.2
D.3
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Among the given complexes, the complex having the highest paramagnetic behaviour is: (At. No. Ti = 22, Cr = 24, Co = 27, Zn = 30)

A.$[Zn(NH_3)_6]^{2+}$
B.$[Ti(NH_3)_6]^{3+}$
C.$[Cr(NH_3)_6]^{3+}$
D.$[Co(NH_3)_6]^{3+}$
MediumSolve

Mg is present in:

A.Chlorophyll
B.Haemoglobin
C.Vitamin-B12
D.Vitamin-B
EasySolve

The complexes $[\text{Co}(\text{NH}_3)_6][\text{Cr}(\text{CN})_6]$ and $[\text{Cr}(\text{NH}_3)_6][\text{Co}(\text{CN})_6]$ are examples of:

A.Ionisation isomerism
B.Coordination isomerism
C.Geometrical isomerism
D.Linkage isomerism
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The coordination compound that gives the maximum number of isomers is:

A.$[Co(NH_3)_4Cl_2]$
B.$[Ni(en)(NH_3)_4]^{2+}$
C.$[Ni(C_2O_4)(en)_2]$
D.$[Cr(SCN)_2(NH_3)_4]^+$
HardSolve

$[Cu(NH_3)_4]^{2+}$ reacts with $HNO_3$ in excess of water and gives:

A.$Cu(OH)_2$
B.$Cu(NO_3)_2$
C.$[Cu(H_2O)_4]^{2+}$
D.None of the above
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CFSE (in the octahedral field) will be maximum in: (Atomic number Co = 27)

A.[Co(H₂O)₆]³⁺
B.[Co(NH₃)₆]³⁺
C.[Co(CN)₆]³⁻
D.[Co(C₂O₄)₃]³⁻
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The IUPAC name of the following complex is: $[Ag(H_2O)_2][Ag(CN)_2]$

A.Diaquasilver(I) dicyanidoargentate(I)
B.Dicyanidosilver(II) diaquaargentate(II)
C.Diaquasilver(II) dicyanidoargentate(II)
D.Dicyanidosilver(I) diaquaargentate(I)
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