Coordination Chemistry: Master the Fundamentals of Complex Formation and Bonding

Question 1

Which species is NOT an isomer of [Co(NH3)4Cl2]+?

Accepted Answer

[Co(NH3)3Cl3]

Answer

cis-[Co(NH3)4Cl2]+

Answer

trans-[Co(NH3)4Cl2]+

Question 2

Provide the IUPAC name for the complex [Co(NH3)4Cl2]+:

Accepted Answer

Tetraamminecobalt(II) chloride

Answer

Potassium tetrachloroamminecobaltate(III)

Answer

Hexamminecobalt(III) chloride

Answer

Dichlorodiamminecobalt(III) chloride

Question 3

A complex with a high value of crystal field stabilization energy (CFSE) is likely to be:

Accepted Answer

More stable

Answer

Less stable

Answer

More reactive

Answer

Less reactive

Question 4

Which of the following is NOT an application of coordination chemistry in medicine?

Accepted Answer

Food preservation

Answer

Cancer treatment

Answer

Imaging techniques

Answer

Drug delivery

Question 5

A characteristic of a strong-field ligand is that it:

Accepted Answer

Causes low-spin complexes

Answer

Causes high-spin complexes

Answer

Weakens the metal-ligand bond

Answer

Stabilizes low oxidation states

Question 6

In IUPAC nomenclature, the correct name for the complex [Co(NH3)5Cl]2+ is:

Accepted Answer

Pentaamminechlorocobalt(II) ion

Answer

Hexaamminecobalt(II) chloride

Answer

Pentaamminecobalt(III) chloride

Answer

Tetraamminechlorocobalt(II) ion

Question 7

The coordination number of the central Fe ion in the complex [Fe(CN)6]4- is:

Accepted Answer

6

Answer

4

Answer

5

Answer

7

Question 8

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

Accepted Answer

CN-

Answer

Cl-

Answer

NH3

Answer

H2O

Question 9

Which of the following is an illustration of a homogeneous catalyst?

Accepted Answer

Enzymes in biochemical reactions

Answer

Nickel in the hydrogenation of alkenes

Answer

Sulfuric acid in the esterification of alcohols

Answer

Sodium hydroxide in the saponification of triglycerides

Question 10

The defining feature that distinguishes chelating ligands from non-chelating ligands is:

Accepted Answer

Chelating ligands form ring structures with the metal ion while non-chelating ligands do not.

Answer

Chelating ligands form multiple bonds with the metal ion while non-chelating ligands form only single bonds.

Answer

Chelating ligands are invariably bidentate while non-chelating ligands are always monodentate.

Answer

Chelating ligands enhance the stability of coordination complexes while non-chelating ligands diminish it.

Question 11

The EAN (Effective Atomic Number) rule states that:

Accepted Answer

The total number of electrons in a coordination complex, including the metal ion and ligands, is equal to the atomic number of the metal.

Answer

The number of d electrons in the metal ion matches the number of ligands bonded to it.

Answer

The coordination number of the metal ion is equivalent to the number of ligands connected to it.

Answer

The geometry of a coordination complex is determined solely by the number of d electrons in the metal ion.

Question 12

Which of the following is a type of ligand that can bind to a metal ion through multiple donor atoms, forming a ring structure?

Accepted Answer

Chelating

Answer

Monodentate

Answer

Bidentate

Answer

Ambidentate

Question 13

Which of the following reactions represents a ligand exchange reaction, where one ligand is replaced by another?

Accepted Answer

[Cu(en)2]2+ + 2NH3 → [Cu(en)(NH3)2]+ + en

Answer

[Co(NH3)6]Cl3 + 3H2O → [Co(NH3)3(H2O)3]Cl3 + 3NH3

Answer

[Fe(CN)6]4- + 6H+ → [Fe(H2O)6]2+ + 6CN-

Answer

[PtCl4]2- + 2NH3 → [Pt(NH3)2Cl2]

Question 14

What is the coordination sphere of the iron ion in the complex [Fe(CN)6]4-? The complex has octahedral geometry.

Accepted Answer

Octahedral

Answer

Tetrahedral

Answer

Square planar

Answer

Trigonal bipyramidal

Question 15

What is the biological function of the coordination complex in hemoglobin?

Accepted Answer

Oxygen transport

Answer

Electron transfer

Answer

Enzymatic catalysis

Answer

Hormone regulation

Question 16

What is the coordination number of the iron ion in the complex [Fe(NH3)6]3+?

Accepted Answer

6

Answer

4

Answer

8

Answer

12

Question 17

What is the most common geometry for a square planar complex?

Accepted Answer

Square planar

Answer

Tetrahedral

Answer

Octahedral

Answer

Trigonal pyramidal

Question 18

What is the IUPAC name of the complex [Co(NH3)5Cl]Cl2?

Accepted Answer

Pentaamminechlorocobalt(III) chloride

Answer

Hexaamminecobalt(II) chloride

Answer

Pentaamminecobalt(III) dichloride

Answer

Tetraamminecobalt(II) chloride

Question 19

Which characteristic is unique to high-spin complexes?

Accepted Answer

High magnetic moment

Answer

Low magnetic moment

Answer

Square planar geometry

Answer

Diamagnetic behavior

Question 20

What type of reaction occurs when a ligand replaces another ligand in a coordination complex?

Accepted Answer

Substitution reaction

Answer

Redox reaction

Answer

Acid-base reaction

Answer

Precipitation reaction

Question 21

What is the molecular geometry of the complex [PtCl4]2-?

Accepted Answer

Square planar

Answer

Tetrahedral

Answer

Octahedral

Answer

Trigonal bipyramidal