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NEET CHEMISTRYCoordination CompoundsMedium

Question

CuSO4CuSO_4 when reacts with KCN forms CuCN, which is insoluble in water. It is soluble in excess of KCN, due to the formation of the following complex:

A

K2[Cu(CN)4]K_2[Cu(CN)_4]

B

K3[Cu(CN)4]K_3[Cu(CN)_4]

C

CuCN2CuCN_2

D

Cu[KCu(CN)4]Cu[KCu(CN)_4]

Step-by-Step Solution

When CuSO4CuSO_4 reacts with KCNKCN, cupric cyanide Cu(CN)2Cu(CN)_2 is initially formed, which being unstable rapidly decomposes to give a white precipitate of cuprous cyanide CuCNCuCN and cyanogen gas (CN)2(CN)_2. 2CuSO4+4KCN→2CuCN↓+(CN)2↑+2K2SO42CuSO_4 + 4KCN \rightarrow 2CuCN \downarrow + (CN)_2 \uparrow + 2K_2SO_4

The insoluble cuprous cyanide (CuCNCuCN) then dissolves in excess of KCNKCN to form a highly stable and soluble complex, potassium tetracyanidocuprate(I), K3[Cu(CN)4]K_3[Cu(CN)_4]. CuCN+3KCN→K3[Cu(CN)4]CuCN + 3KCN \rightarrow K_3[Cu(CN)_4]

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 Compoundsreactsinsolublesolubleexcessformation

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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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A.$[Zn(NH_3)_6]^{2+}$
B.$[Ti(NH_3)_6]^{3+}$
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D.$[Co(NH_3)_6]^{3+}$
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Mg is present in:

A.Chlorophyll
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C.Vitamin-B12
D.Vitamin-B
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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
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The coordination compound that gives the maximum number of isomers is:

A.$[Co(NH_3)_4Cl_2]$
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$[Cu(NH_3)_4]^{2+}$ reacts with $HNO_3$ in excess of water and gives:

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CFSE (in the octahedral field) will be maximum in: (Atomic number Co = 27)

A.[Co(H₂O)₆]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)
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