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Coordination Compounds · Question 38

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1

The number of paramagnetic complexes among [FeF6]3-, [Fe(CN)6]3-, [Mn(CN)6]3-, [Co(C2O4)3]3-, [MnCl6]3-, and [CoF6]3-, which involve d2sp3 hybridization is .

Answer

2

Solution

Inner orbital (d2sp3) complexes are formed with strong field ligands (CN-, C2O42- with Co3+); weak field F- and Cl- give outer orbital (sp3d2) complexes.

[FeF6]3-: Fe3+ (3d5), sp3d2, 5 unpaired electrons

[Fe(CN)6]3-: Fe3+ (3d5), d2sp3, 1 unpaired electron paramagnetic

[Mn(CN)6]3-: Mn3+ (3d4), d2sp3, 2 unpaired electrons paramagnetic

[Co(C2O4)3]3-: Co3+ (3d6), d2sp3, 0 unpaired electrons diamagnetic

[MnCl6]3-: Mn3+ (3d4), sp3d2, 4 unpaired electrons

[CoF6]3-: Co3+ (3d6), sp3d2, 4 unpaired electrons

paramagnetic complexes with d2sp3 hybridisation = 2

Answer: 2

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Keep practising — Coordination Compounds

2

Match List - I with List - II. Choose the correct answer from the options given below :

  1. A-I, B-III, C-II, D-IV
  2. A-II, B-III, C-IV, D-I
  3. A-I, B-IV, C-IV, D-III
  4. A-III, B-I, C-II, D-IV
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3

The number of unpaired electrons responsible for the paramagnetic nature of the following complex species are respectively : [Fe(CN)6]3-, [FeF6]3-, [CoF6]3-, [Mn(CN)6]3-

  1. 1, 5, 4, 2
  2. 1, 4, 4, 2
  3. 1, 5, 5, 2
  4. 1, 1, 4, 2
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4

The number of paramagnetic metal complex species among [Co(NH3)6]3+, [Co(C2O4)3]3-, [MnCl6]3-, [Mn(CN)6]3-, [CoF6]3-, [Fe(CN)6]3- and [FeF6]3- with same number of unpaired electrons is .

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5

Which one of the following complexes will have o = 0 and = 5.96 B.M.?

  1. [FeF6]4-
  2. [Mn(SCN)6]4-
  3. [Co(NH3)6]3+
  4. [Fe(CN)6]4-
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6

Number of stereoisomers possible for the complexes, [CrCl3(py)3] and [CrCl2(ox)2]3- are respectively (py = pyridine, ox = oxalate)

  1. 3 & 3
  2. 2 & 3
  3. 1 & 2
  4. 2 & 2
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7

'X' is the number of electrons in t2g orbitals of the most stable complex ion among [Fe(NH3)6]3+, [FeCl6]3-, [Fe(C2O4)3]3- and [Fe(H2O)6]3+. The nature of oxide of vanadium of the type V2OX is :

  1. Amphoteric
  2. Acidic
  3. Basic
  4. Neutral
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8

The correct order of [FeF6]3-, [CoF6]3-, [Ni(CO)4] and [Ni(CN)4]2- complex species based on the number of unpaired electrons present is:

  1. [CoF6]3- > [FeF6]3- > [Ni(CO)4] > [Ni(CN)4]2-
  2. [FeF6]3- > [CoF6]3- > [Ni(CN)4]2- > [Ni(CO)4]
  3. [FeF6]3- > [CoF6]3- > [Ni(CN)4]2- = [Ni(CO)4]
  4. [Ni(CN)4]2- > [FeF6]3- > [CoF6]3- > [Ni(CO)4]
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9

A metal complex with a formula MCl4 3NH3 is involved in sp3d2 hybridisation. It upon reaction with excess of AgNO3 solution gives 'x' moles of AgCl. Consider 'x' is equal to the number of lone pairs of electrons present in the central atom of BrF5. Then the number of geometrical isomers exhibited by the complex is .

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10

The correct order of the complexes [Co(NH3)5(H2O)]3+ (A), [Co(NH3)6]3+ (B), [Co(CN)6]3- (C) and [CoCl(NH3)5]2+ (D) in terms of wavelength of light absorbed is

  1. D > C > B > A
  2. C > B > A > D
  3. D > A > B > C
  4. C > B > D > A
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11

The number of optical isomers exhibited by the iron complex (A) obtained from the following reaction is . FeCl3 + KOH + H2C2O4 A

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