Chemistry

Coordination Chemistry

319 Questions

Coordination chemistry focuses on coordination compounds, their structures, and their magnetic properties. The questions cover primary and secondary valencies, ligand types, and geometries of complexes. This topic is heavily tested in chemistry competitive exams and requires a good grasp of molecular structures.

primary and secondary valencycomplex geometriesligand field theorymagnetic properties of complexesisomerism in complexes

Coordination Chemistry Questions

Multiple choice chemistry solid state classification of crystalline solids classification of solids introduction to solids

Which of the following compounds represent represent a normal $2 : 3$ spinel structure?

  1. $Mg^{II} Al _{2}^{III}O _{4}$
  2. $Co^{II} (Co^{III}) _{2}O _{4}$
  3. $Zn(TiZn) O _{4}$
  4. $Ni(CO) _{4}$
Reveal answer Fill a bubble to check yourself
A,B Correct answer
Explanation

In $2:3$ spinel structure                                        General formula is $A^{+2}B _2^{+3}O _4$

$A^{+2} : \cfrac {1}{8}\times Tetrahedral\quad  voids$                    $B^{+3} : \cfrac {1}{2} \times Octahedral\quad voids$        $O^{2-}:FCC\quad lattice$

Only $Mg^{+2}Al _2^{+3}O _4$  and  $Co^{2+}(Co^{3+}) _2O _4$ satisfies the above conditions.

$\longrightarrow$ Also, in option (C) $Ti$ have $+4$ oxidtion state.

Ans-(A), (B)

Multiple choice

Which of the following is an example of a coordination complex?

  1. Sodium chloride

  2. Water

  3. Hemoglobin

  4. Carbon dioxide
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Hemoglobin is a coordination complex, where an iron ion is surrounded by a porphyrin ring and other ligands.

Multiple choice

What is the role of a ligand in an organometallic compound?

  1. To donate electrons to the metal center.

  2. To accept electrons from the metal center.

  3. To stabilize the metal center.

  4. All of the above.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Ligands donate electrons to the metal center, accept electrons from the metal center, and stabilize the metal center.

Multiple choice

Which library is designed for electronic structure calculations using the density matrix renormalization group (DMRG) method?

  1. Psi4

  2. Turbomole

  3. NWChem

  4. ALPS
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

ALPS (Algorithms and Libraries for Physics Simulations) is a library for electronic structure calculations using the density matrix renormalization group (DMRG) method.

Multiple choice

The splitting of d-orbitals in a coordination complex is primarily caused by:

  1. The electrostatic repulsion between electrons in the d-orbitals

  2. The interaction between the metal ion and the ligands

  3. The Jahn-Teller effect

  4. The Hund's rule
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In Ligand Field Theory, the splitting of d-orbitals is primarily caused by the interaction between the metal ion and the ligands. This interaction is influenced by the nature of the ligands, their symmetry, and the number of electrons in the d-orbitals.

Multiple choice

Which of the following factors affects the magnitude of the crystal field splitting energy?

  1. The charge of the metal ion

  2. The number of d-electrons

  3. The geometry of the coordination complex

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The magnitude of the crystal field splitting energy is influenced by several factors, including the charge of the metal ion, the number of d-electrons, and the geometry of the coordination complex. These factors collectively determine the strength of the interaction between the metal ion and the ligands.

Multiple choice

Which of the following statements is true about tetrahedral complexes?

  1. They exhibit a larger crystal field splitting energy compared to octahedral complexes

  2. They have a higher degree of orbital overlap between the metal ion and the ligands

  3. They are more stable than octahedral complexes

  4. None of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Tetrahedral complexes generally exhibit a smaller crystal field splitting energy, a lower degree of orbital overlap, and are less stable compared to octahedral complexes.

Multiple choice

The Jahn-Teller effect refers to:

  1. The distortion of a coordination complex from its regular geometry

  2. The splitting of d-orbitals in a coordination complex

  3. The pairing of electrons in d-orbitals

  4. The formation of coordination complexes
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The Jahn-Teller effect describes the distortion of a coordination complex from its regular geometry in order to lower its energy. This distortion is caused by the presence of unpaired electrons in the d-orbitals of the metal ion.

Multiple choice

Which of the following is a consequence of the Jahn-Teller effect?

  1. A decrease in the crystal field splitting energy

  2. An increase in the stability of the coordination complex

  3. A change in the coordination geometry

  4. All of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The Jahn-Teller effect primarily leads to a change in the coordination geometry of the complex in order to lower its energy. It does not necessarily affect the crystal field splitting energy or the stability of the complex.

Multiple choice

The spectrochemical series arranges ligands based on their ability to:

  1. Split d-orbitals

  2. Form coordination complexes

  3. Donate electrons to metal ions

  4. Accept electrons from metal ions
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The spectrochemical series arranges ligands based on their ability to split d-orbitals in a coordination complex. This series is useful in predicting the magnitude of the crystal field splitting energy and the electronic configuration of the metal ion.

Multiple choice

Which of the following ligands is a strong-field ligand?

  1. Cl-

  2. NH3

  3. CN-

  4. H2O
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

CN- is a strong-field ligand due to its high electronegativity and the ability to form strong covalent bonds with metal ions. It causes a large splitting of d-orbitals and stabilizes low-spin complexes.

Multiple choice

Which of the following ligands is a weak-field ligand?

  1. F-

  2. CO

  3. en

  4. NO2-
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

CO is a weak-field ligand due to its low electronegativity and the ability to form π-backbonding interactions with metal ions. It causes a small splitting of d-orbitals and stabilizes high-spin complexes.

Multiple choice

The electronic configuration of a metal ion in a coordination complex can be determined using:

  1. Ligand Field Theory

  2. Molecular Orbital Theory

  3. Valence Bond Theory

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The electronic configuration of a metal ion in a coordination complex can be determined using Ligand Field Theory, Molecular Orbital Theory, or Valence Bond Theory. These theories provide different perspectives on the bonding and electronic structure of coordination complexes.

Multiple choice

Which of the following is NOT a type of isomerism observed in coordination complexes?

  1. Structural isomerism

  2. Geometrical isomerism

  3. Ligand isomerism

  4. Coordination isomerism
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Coordination isomerism is not a type of isomerism observed in coordination complexes. The other three options, structural isomerism, geometrical isomerism, and ligand isomerism, are common types of isomerism encountered in coordination chemistry.

Multiple choice

The stability of a coordination complex is primarily determined by:

  1. The strength of the metal-ligand bond

  2. The number of d-electrons in the metal ion

  3. The geometry of the coordination complex

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The stability of a coordination complex is influenced by several factors, including the strength of the metal-ligand bond, the number of d-electrons in the metal ion, and the geometry of the coordination complex.