Chapter 19, Problem 33E

(a)

Interpretation Introduction

Interpretation: The term isomer needs to be explained with examples.

Concept Introduction:

A coordination complex is composed of two main parts; metal atom/ ion and ligand. Ligands are the atom/ group of atom/ ion that can donate its extra pair of electrons to the electron deficient metal cation. It leads to the formation of coordinate bond between metal ion and ligand.

A metal complex can be show as ${\text{[ML}}_{\text{n}}\text{]}$ . Here M indicates the metal atom or ion whereas L indicates the ligands which are present in ‘n’ numbers. The coordination number defines the number of coordinate bonds between metal and ligand.

Answer to Problem 33E

Isomers can be defined as the coordination complexes or molecules which have same formula due to same ligands or atoms yet they show different properties. Examples: $\text{CoBr(NH}\text{)}{}_{\text{5}}\text{Cl }$ and ${\text{CoCl(NH}}_{\text{3}}{\text{)}}_{\text{5}}\text{Br }$ .

Explanation of Solution

Isomers can be defined as the coordination complexes or molecules which have same formula due to same ligands or atoms yet they show different properties due to different bonding between atoms and groups. For example;

  $\text{CoBr(NH}\text{)}{}_{\text{5}}\text{Cl }$ and ${\text{CoCl(NH}}_{\text{3}}{\text{)}}_{\text{5}}\text{Br }$ are isomers of each other as they have same atoms and metal ion yet they have different properties because ${\text{CoCl(NH}}_{\text{3}}{\text{)}}_{\text{5}}\text{Br }$ has ${\text{Br}}^{\text{-}}$ as counter ion whereas $\text{CoBr(NH}\text{)}{}_{\text{5}}\text{Cl }$ has ${\text{Cl}}^{\text{-}}$ as counter ion.

(b)

Interpretation Introduction

Interpretation: The term structural isomer needs to be explained with examples.

Concept Introduction:

A coordination complex is composed of two main parts; metal atom/ ion and ligand. Ligands are the atom/ group of atom/ ion that can donate its extra pair of electrons to the electron deficient metal cation. It leads to the formation of coordinate bond between metal ion and ligand.

A metal complex can be show as ${\text{[ML}}_{\text{n}}\text{]}$ . Here M indicates the metal atom or ion whereas L indicates the ligands which are present in ‘n’ numbers. The coordination number defines the number of coordinate bonds between metal and ligand.

Answer to Problem 33E

Structural Isomers can be defined as the coordination complexes or molecules which have same formula due to same ligands or atoms yet they show different properties. Hence they have difference in the bonding of bonded ligands or counter ions. Examples: $\text{CoCl(NH}\text{)}{}_{\text{5}}\text{I}$ and ${\text{CoI(NH}}_{\text{3}}{\text{)}}_{\text{5}}\text{Cl}$ .

Explanation of Solution

Isomers can be defined as the coordination complexes or molecules which have same formula due to same ligands or atoms yet they show different properties due to different bonding between atoms and groups. For example;

  $\text{CoCl(NH}\text{)}{}_{\text{5}}\text{I}$ and ${\text{CoI(NH}}_{\text{3}}{\text{)}}_{\text{5}}\text{Cl}$ are isomers of each other as they have same atoms and metal ion yet they have different properties because $\text{CoCl(NH}\text{)}{}_{\text{5}}\text{I}$ has ${\text{I}}^{\text{-}}$ as counter ion whereas ${\text{CoI(NH}}_{\text{3}}{\text{)}}_{\text{5}}\text{Cl}$ has ${\text{Cl}}^{\text{-}}$ as counter ion.

(c)

Interpretation Introduction

Interpretation: The term stereoisomer needs to be explained with examples.

Concept Introduction:

A coordination complex is composed of two main parts; metal atom/ ion and ligand. Ligands are the atom/ group of atom/ ion that can donate its extra pair of electrons to the electron deficient metal cation. It leads to the formation of coordinate bond between metal ion and ligand.

A metal complex can be show as ${\text{[ML}}_{\text{n}}\text{]}$ . Here M indicates the metal atom or ion whereas L indicates the ligands which are present in ‘n’ numbers. The coordination number defines the number of coordinate bonds between metal and ligand.

Answer to Problem 33E

Stereoisomer can be defined as the coordination complexes or molecules which have same structural formula but different arrangement of bonded atoms or group in 3-D space.

Examples: ${\text{trans-Pt(NH}}_{\text{3}}{\text{)}}_{\text{2}}{\text{Cl}}_{\text{2}}$ and ${\text{cis-Pt(NH}}_{\text{3}}{\text{)}}_{\text{2}}{\text{Cl}}_{\text{2}}$ .

Explanation of Solution

Isomers can be defined as the coordination complexes or molecules which have same formula due to same ligands or atoms yet they show different properties due to different bonding between atoms and groups. Stereoisomer can be defined as the coordination complexes or molecules which have same structural formula but different arrangement of bonded atoms or group in 3-D space. For examples: ${\text{trans-Pt(NH}}_{\text{3}}{\text{)}}_{\text{2}}{\text{Cl}}_{\text{2}}$ and ${\text{cis-Pt(NH}}_{\text{3}}{\text{)}}_{\text{2}}{\text{Cl}}_{\text{2}}$ have exactly same structural formula but the arrangement of bonded ligands in 3-D space is different.

(d)

Interpretation Introduction

Interpretation: The term coordination isomer needs to be explained with examples.

Concept Introduction:

A coordination complex is composed of two main parts; metal atom/ ion and ligand. Ligands are the atom/ group of atom/ ion that can donate its extra pair of electrons to the electron deficient metal cation. It leads to the formation of coordinate bond between metal ion and ligand.

A metal complex can be show as ${\text{[ML}}_{\text{n}}\text{]}$ . Here M indicates the metal atom or ion whereas L indicates the ligands which are present in ‘n’ numbers. The coordination number defines the number of coordinate bonds between metal and ligand.

Answer to Problem 33E

Coordination isomers are the isomers in which both anion and cation complex ions have same molecular formula but different bonding of ligands. For example; ${\text{[Co(NH}}_{\text{3}}{\text{)}}_{\text{6}}\left]\right[{\text{Cr(C}}_{\text{2}}{\text{O}}_{\text{4}}{\text{)}}_{\text{3}}\text{]}$ and ${\text{[Co(C}}_{\text{2}}{\text{O}}_{\text{4}}{\text{)}}_{\text{3}}\left]\right[{\text{Cr(NH}}_{\text{3}}{\text{)}}_{\text{6}}\text{]}$ are coordination isomers.

Explanation of Solution

Structural Isomers can be defined as the coordination complexes or molecules which have same formula due to same ligands or atoms yet they show different properties due to different bonding between atoms and groups. Coordination isomers are a type of structural isomers in which both anion and cation complex ions have same molecular formula but different bonding of ligands.

Hence both cation and anion complex ions interchange their ligands. ${\text{[Co(NH}}_{\text{3}}{\text{)}}_{\text{6}}\left]\right[{\text{Cr(C}}_{\text{2}}{\text{O}}_{\text{4}}{\text{)}}_{\text{3}}\text{]}$ and ${\text{[Co(C}}_{\text{2}}{\text{O}}_{\text{4}}{\text{)}}_{\text{3}}\left]\right[{\text{Cr(NH}}_{\text{3}}{\text{)}}_{\text{6}}\text{]}$ are coordination isomers. Here both complexes have same type of metal ions and ligands yet the cation and anions have different ligands.

(e)

Interpretation Introduction

Interpretation: The term linkage isomer needs to be explained with examples.

Concept Introduction:

A coordination complex is composed of two main parts; metal atom/ ion and ligand. Ligands are the atom/ group of atom/ ion that can donate its extra pair of electrons to the electron deficient metal cation. It leads to the formation of coordinate bond between metal ion and ligand.

A metal complex can be show as ${\text{[ML}}_{\text{n}}\text{]}$ . Here M indicates the metal atom or ion whereas L indicates the ligands which are present in ‘n’ numbers. The coordination number defines the number of coordinate bonds between metal and ligand.

Answer to Problem 33E

Linkage isomers are the isomers which have different bonding atoms in the ambi-dentate ligands.For example; $\text{[Co}\left(\text{ONO}\right){{\text{(NH}}_{\text{3}}\text{)}}_{\text{5}}{\text{]Cl and [Co(NO}}_{\text{2}}{\text{)(NH}}_{\text{3}}{\text{)}}_{\text{5}}\text{]Cl}$ are examples of Linkage isomers.

Explanation of Solution

Structural Isomers can be defined as the coordination complexes or molecules which have same formula due to same ligands or atoms yet they show different properties due to different bonding between atoms and groups. Linkage isomers are a type of structural isomers in which the bonded ligands are ambidentate ligands and have different bonding atoms which form coordination bond with metal ion. Some common examples of ambidentate ligands are ${\text{SCN- \& NCS- and NO}}_{\text{2}}{}^{\text{-}}{\text{ \& ONO}}^{\text{-}}$ . In Nitro and nitrito ligands, the bonding atoms are −N and −O respectively.

  $\text{[Co}\left(\text{ONO}\right){{\text{(NH}}_{\text{3}}\text{)}}_{\text{5}}{\text{]Cl and [Co(NO}}_{\text{2}}{\text{)(NH}}_{\text{3}}{\text{)}}_{\text{5}}\text{]Cl}$ are examples of Linkage isomers. Here −O is the bonding atom in $\text{[Co}\left(\text{ONO}\right){{\text{(NH}}_{\text{3}}\text{)}}_{\text{5}}\text{]Cl}$ whereas −N is the bonding atom in ${\text{[Co(NO}}_{\text{2}}{\text{)(NH}}_{\text{3}}{\text{)}}_{\text{5}}\text{]Cl}$ .

(f)

Interpretation Introduction

Interpretation: The term geometrical isomers needs to be explained with examples.

Concept Introduction:

A coordination complex is composed of two main parts; metal atom/ ion and ligand. Ligands are the atom/ group of atom/ ion that can donate its extra pair of electrons to the electron deficient metal cation. It leads to the formation of coordinate bond between metal ion and ligand.

A metal complex can be show as ${\text{[ML}}_{\text{n}}\text{]}$ . Here M indicates the metal atom or ion whereas L indicates the ligands which are present in ‘n’ numbers. The coordination number defined the number of coordinate bonds between metal and ligand.

Answer to Problem 33E

Geometrical isomers can be defined as the complexes or molecules which have same structural formula but different orientation of bonded ligands in the plane.

Examples: ${\text{trans-Pt(NH}}_{\text{3}}{\text{)}}_{\text{2}}{\text{Cl}}_{\text{2}}$ and ${\text{cis-Pt(NH}}_{\text{3}}{\text{)}}_{\text{2}}{\text{Cl}}_{\text{2}}$ .

Explanation of Solution

Stereoisomer can be defined as the coordination complexes or molecules which have same structural formula but different arrangement of bonded atoms or group in 3-D space.

Geometrical isomers are the type of stereoisomers which can be defined as the complexes or molecules which have same structural formula but different orientation of bonded ligands in the plane.

For example, ${\text{trans-Pt(NH}}_{\text{3}}{\text{)}}_{\text{2}}{\text{Cl}}_{\text{2}}$ and ${\text{cis-Pt(NH}}_{\text{3}}{\text{)}}_{\text{2}}{\text{Cl}}_{\text{2}}$ ; in trans-isomer, similar ligands are placed in opposite direction whereas in cis-isomer same ligands are placed in same direction.

(g)

Interpretation Introduction

Interpretation: The term optical isomers need to be explained with examples.

Concept Introduction:

A coordination complex is composed of two main parts; metal atom/ ion and ligand. Ligands are the atom/ group of atom/ ion that can donate its extra pair of electrons to the electron deficient metal cation. It leads to the formation of coordinate bond between metal ion and ligand.

A metal complex can be show as ${\text{[ML}}_{\text{n}}\text{]}$ . Here M indicates the metal atom or ion whereas L indicates the ligands which are present in ‘n’ numbers. The coordination number defines the number of coordinate bonds between metal and ligand.

Answer to Problem 33E

Optical isomers can be defined as the complexes or molecules which have same structural formula but different orientation of bonded ligands in the plane therefore they show different optical properties.

Examples: ${\text{[Co}{\left(\text{en}\right)}_{\text{3}}\text{]}}^{\text{3+}}$ can show d and l isomers.

Explanation of Solution

Stereoisomer can be defined as the coordination complexes or molecules which have same structural formula but different arrangement of bonded atoms or group in 3-D space.

Optical isomers can be defined as the complexes or molecules which have same structural formula but different orientation of bonded ligands in the plane therefore they show different optical properties.

For example, ${\text{[Co}{\left(\text{en}\right)}_{\text{3}}\text{]}}^{\text{3+}}$ can exist in dextrorotatory and levorotatory isomers which can rotate the plane polarize clockwise and anti-clockwise respectively.