Chapter 20, Problem 20.16QP

(a)

Interpretation Introduction

Interpretation: The systematic name for the given compound has to be predicted.

Concept Introduction:

Systematic naming is the standard name given in a systematic way to a unique complex compound.

Systematic naming for the complex compound can be given based on the few important guidelines given below:

1. 1. The name of the ligand is followed by the name of the central metal cation of a complex compound.
2. 2. If there is more than one type of ligand, then their names are arranged in an alphabetical order.
3. 3. When more than one same type of ligands are present, then the Greek prefixes such as di, tri, tetra, penta, and hexa are used to specify their count such as 1,2,3,4.5 and 6 respectively.
4. 4. The oxidation number of the metal is represented in roman numerals immediately following the metal ion name.
5. 5. If the net charge of the complex ion is -ve, then the central metal name should end with the suffix word –ate. Whereas if the net charge of the complex ion is +ve, then the central metal name should end with the suffix word –um.
6. 6. The isomeric form of a given compound should also be mentioned. cis - means that the compound is in the cis-isomeric form in which the different types of ligands will be placed on the same side to each other. trans - means that the compound is in the trans -isomeric form in which the different types of ligands are placed on the opposite side to each other.
7. 7. The more than one count of the poly-dentate ligands should be specified as bis, tris respective to the count 2 and 3.
8. 8. Poly-dentate ligand means ligands which can donate more than one lone pair of electrons. The various polydentate ligands are as follows:
   1. 1) Mono-dentate ligand: The ligand that can donate one electron pair to the central metal atom.
   2. 2) Bi-dentate ligand: The ligand that can donate two electron pairs to the central metal atom.
   3. 3) Tri-dentate ligand: The ligand that can donate three electron pairs to the central metal atom.
   4. 4) Tetra-dentate ligand: The ligand that can donate four electron pairs to the central metal atom.
   5. 5) Penta-dentate ligand: The ligand that can donate five electron pairs to the central metal atom.

       and so on…

9. 9. The name of the ions outside the co-ordination sphere should be named generally without the need mentioning its count as the prefix name because such ionic species are not considered as ligands. The same has to be followed for naming the counter ions which will be present before the complex.

Answer to Problem 20.16QP

The systematic name for ${{\text{[cis-Co(en)}}_2{\text{Cl}}_{\text{2}}\text{]}}^{\text{+}}$ is: $\text{cis-dichlorobis(ethylenediammine)cobalt}\left(\text{III}\right)\text{.}$

Explanation of Solution

• The given compound is ${{\text{[cis-Co(en)}}_2{\text{Cl}}_{\text{2}}\text{]}}^{\text{+}}$.

cis - means that the compound is in the cis-isomeric form in which the different types of ligands will be placed on the same side to each other.

$\text{en}\to \text{named}\text{as}\text{ethylenediammine}$. It is a ligand with neutral charge. It is a bi-dentate ligand. Since there are two $\text{en}$, so the name of the ligand should hold the prefix word as

“bis”.

$\text{Cl}\to \text{named}\text{as}\text{chloro}$. It is a ligand with negative charge -1. There are two $\text{Cl}$ ligands inside the complex. So, the name of the ligand should hold the prefix name as “di-“.

• The oxidation state of the central metal cobalt atom can be calculated as follows:

${{\text{[cis-Co(en)}}_2{\text{Cl}}_{\text{2}}\text{]}}^{\text{+}}$

$\begin{array}{l}\text{Ligand-}\text{Cl}\text{has}\text{the}\text{charge}\text{as}-1.\\ 2\left(\text{Cl}\right)\text{have}\text{the}\text{charge}\text{as}2\times -1=-2\end{array}$

$\begin{array}{l}\text{Ligand-}\text{en}\text{has}\text{the}\text{charge}\text{as}0.\\ 2\left(\text{en}\right)\text{have}\text{the}\text{charge}\text{as}2\times 0=0\end{array}$

$\text{Let}\text{the}\text{oxidation}\text{number}\text{of}\text{Co}\text{be}{}^{\text{'}}\text{x}{}^{\text{'}}$

• The sum of the oxidation states of the ligands and the central metal can be equated to the net charge of the complex ion to obtain the oxidation number of the central metal.
•  The net charge of the complex is shown as +1.
• Let the unknown oxidation number of the central metal atom be “x”.

$\begin{array}{c}\text{x}+0-2=+1\\ \text{x}=+1+2\\ =+3\\ \therefore \text{The}\text{oxidation}\text{number}\text{of}\text{Co}\text{is}+3\end{array}$

• The names of the two ligands should be alphabetically arranged.
• The name of the metal ion should follow the name of the ligand.
• The name of the central metal ion should be immediately followed by its oxidation number in roman numerals within brackets.
• There should be no space in between the name and the brackets.

Based on the above discussion, the systematic name of the given complex compound can be given as $\text{cis-dichlorobis(ethylenediammine)cobalt}\left(\text{III}\right)\text{.}$

(b)

Interpretation Introduction

Interpretation: The systematic name for the given compound has to be predicted.

Concept Introduction:

Systematic naming is the standard name given in a systematic way to a unique complex compound.

Systematic naming for the complex compound can be given based on the few important guidelines given below:

1. 1. The name of the ligand is followed by the name of the central metal cation of a complex compound.
2. 2. If there is more than one type of ligand, then their names are arranged in an alphabetical order.
3. 3. When more than one same type of ligands are present, then the Greek prefixes such as di, tri, tetra, penta, and hexa are used to specify their count such as 1,2,3,4.5 and 6 respectively.
4. 4. The oxidation number of the metal is represented in roman numerals immediately following the metal ion name.
5. 5. If the net charge of the complex ion is -ve, then the central metal name should end with the suffix word –ate. Whereas if the net charge of the complex ion is +ve, then the central metal name should end with the suffix word –um.
6. 6. The isomeric form of a given compound should also be mentioned. cis - means that the compound is in the cis-isomeric form in which the different types of ligands will be placed on the same side to each other. trans - means that the compound is in the trans -isomeric form in which the different types of ligands are placed on the opposite side to each other.
7. 7. The more than one count of the poly-dentate ligands should be specified as bis, tris respective to the count 2 and 3.
8. 8. Poly-dentate ligand means ligands which can donate more than one lone pair of electrons. The various polydentate ligands are as follows:
   1. 1) Mono-dentate ligand: The ligand that can donate one electron pair to the central metal atom.
   2. 2) Bi-dentate ligand: The ligand that can donate two electron pairs to the central metal atom.
   3. 3) Tri-dentate ligand: The ligand that can donate three electron pairs to the central metal atom.
   4. 4) Tetra-dentate ligand: The ligand that can donate four electron pairs to the central metal atom.
   5. 5) Penta-dentate ligand: The ligand that can donate five electron pairs to the central metal atom.

       and so on…

9. 9. The name of the ions outside the co-ordination sphere should be named generally without the need mentioning its count as the prefix name because such ionic species are not considered as ligands. The same has to be followed for naming the counter ions which will be present before the complex.

Answer to Problem 20.16QP

The systematic name of ${\text{[Pt(NH}}_{\text{3}}{\text{)}}_5{\text{Cl]Cl}}_3$ is $\text{pentaamminechloroplatinum}\left(\text{IV}\right)\text{Chloride}\text{.}$

Explanation of Solution

• The given compound is ${\text{[Pt(NH}}_{\text{3}}{\text{)}}_5{\text{Cl]Cl}}_3$.

${\text{NH}}_{\text{3}}\to \text{named}\text{as}\text{ammine}$. It is a ligand with neutral charge. There are five ${\text{NH}}_{\text{3}}$ ligands. So, the name of the ligand should hold the prefix name as “penta-“.

$\text{Cl}\to \text{named}\text{as}\text{chloro}$. It is a ligand with negative charge -1. There is only one $\text{Cl}$ atom inside the complex, so the name of the ligand can be named generally as it is whereas there are three $\text{Cl}$ ions outside the complex which are not ligands so the name should be given as “chloride”.

• The oxidation state of the central metal platinum atom can be calculated as follows:

${\text{[Pt(NH}}_{\text{3}}{\text{)}}_5{\text{Cl]Cl}}_3$

$\begin{array}{l}\text{Ligand-}\text{Cl}\text{has}\text{the}\text{charge}\text{as}-1.\\ 1\left(\text{Cl}\right)\text{has}\text{the}\text{charge}\text{as}1\times -1=-1\end{array}$

• The three chlorine atoms outside the complex contribute the charge of -3. In order to balance this charge the complex holds the net charge as +3.

$\begin{array}{l}\text{Ligand-}{\text{NH}}_{\text{3}}\text{has}\text{the}\text{charge}\text{as}0.\\ 5\left({\text{NH}}_{\text{3}}\right)\text{have}\text{the}\text{charge}\text{as}5\times 0=0\end{array}$

• The sum of the oxidation states of the ligands and the central metal can be equated to the net charge of the complex ion to obtain the oxidation number of the central metal.
• The net charge of the complex is known to be +3
• $\text{Let}\text{the}\text{oxidation}\text{number}\text{of}\text{Pt}\text{be}{}^{\text{'}}\text{x}{}^{\text{'}}$

$\begin{array}{c}\text{x}+0-1=+3\\ \text{x}=+1+3\\ =+4\\ \therefore \text{The}\text{oxidation}\text{number}\text{of}\text{Pt}\text{is}+4\end{array}$

• The names of the two ligands should be alphabetically arranged.
• The name of the metal ion should follow the name of the ligand.
• The name of the central metal ion should be immediately followed by its oxidation number in roman numerals within brackets.
• There should be no space in between the name and the brackets.

Based on the above discussion, the systematic name of the given complex compound can be given as $\text{pentaamminechloroplatinum}\left(\text{IV}\right)\text{Chloride}\text{.}$

(c)

Interpretation Introduction

Interpretation: The systematic name for the given compound has to be predicted.

Concept Introduction:

Systematic naming is the standard name given in a systematic way to a unique complex compound.

Systematic naming for the complex compound can be given based on the few important guidelines given below:

1. 1. The name of the ligand is followed by the name of the central metal cation of a complex compound.
2. 2. If there is more than one type of ligand, then their names are arranged in an alphabetical order.
3. 3. When more than one same type of ligands are present, then the Greek prefixes such as di, tri, tetra, penta, and hexa are used to specify their count such as 1,2,3,4.5 and 6 respectively.
4. 4. The oxidation number of the metal is represented in roman numerals immediately following the metal ion name.
5. 5. If the net charge of the complex ion is -ve, then the central metal name should end with the suffix word –ate. Whereas if the net charge of the complex ion is +ve, then the central metal name should end with the suffix word –um.
6. 6. The isomeric form of a given compound should also be mentioned. cis - means that the compound is in the cis-isomeric form in which the different types of ligands will be placed on the same side to each other. trans - means that the compound is in the trans -isomeric form in which the different types of ligands are placed on the opposite side to each other.
7. 7. The more than one count of the poly-dentate ligands should be specified as bis, tris respective to the count 2 and 3.
8. 8. Poly-dentate ligand means ligands which can donate more than one lone pair of electrons. The various polydentate ligands are as follows:
   1. 1) Mono-dentate ligand: The ligand that can donate one electron pair to the central metal atom.
   2. 2) Bi-dentate ligand: The ligand that can donate two electron pairs to the central metal atom.
   3. 3) Tri-dentate ligand: The ligand that can donate three electron pairs to the central metal atom.
   4. 4) Tetra-dentate ligand: The ligand that can donate four electron pairs to the central metal atom.
   5. 5) Penta-dentate ligand: The ligand that can donate five electron pairs to the central metal atom.

       and so on…

9. 9. The name of the ions outside the co-ordination sphere should be named generally without the need mentioning its count as the prefix name because such ionic species are not considered as ligands. The same has to be followed for naming the counter ions which will be present before the complex.

Answer to Problem 20.16QP

The systematic name of ${\text{[Co(NH}}_{\text{3}}{\text{)}}_{\text{6}}{\text{]Cl}}_{\text{3}}$ is $\text{hexaamminecobalt}\left(\text{III}\right)\text{chloride}\text{.}$

Explanation of Solution

• The given compound is ${\text{[Co(NH}}_{\text{3}}{\text{)}}_{\text{6}}{\text{]Cl}}_{\text{3}}$.

${\text{NH}}_{\text{3}}\to \text{named}\text{as}\text{ammine}$. It is a ligand with neutral charge. There are six ${\text{NH}}_{\text{3}}$ ligands. So, the name of the ligand should hold the prefix name as “hexa-“.

$\text{Cl}\to \text{named}\text{as}\text{chloro}$. It is a ligand with negative charge -1. There are three $\text{Cl}$ ions outside the complex which are not ligands so the name should be given as “chloride”.

• The oxidation state of the central metal cobalt atom can be calculated as follows:

${\text{[Co(NH}}_{\text{3}}{\text{)}}_{\text{6}}{\text{]Cl}}_{\text{3}}$

$\text{Ligand-}\text{Cl}\text{has}\text{the}\text{charge}\text{as}-1.$

• The three chlorine atoms outside the complex contribute the charge of -3. In order to balance this charge the complex holds the net charge as +3.

$\begin{array}{l}\text{Ligand-}{\text{NH}}_{\text{3}}\text{has}\text{the}\text{charge}\text{as}0.\\ 6\left({\text{NH}}_{\text{3}}\right)\text{have}\text{the}\text{charge}\text{as}6\times 0=0\end{array}$

• The sum of the oxidation states of the ligands and the central metal can be equated to the net charge of the complex ion to obtain the oxidation number of the central metal.
• The net charge of the complex be +3.
• $\text{Let}\text{the}\text{oxidation}\text{number}\text{of}\text{Pt}\text{be}{}^{\text{'}}\text{x}{}^{\text{'}}$

$\begin{array}{c}\text{x}+0=+3\\ \text{x}=+3\\ \therefore \text{The}\text{oxidation}\text{number}\text{of}\text{Co}\text{is}+3\end{array}$

• Since there are only neutral inside the complex, hence the oxidation number of the complex is being the net charge itself.
• The name of the metal ion should follow the name of the ligand.
• The name of the central metal ion should be immediately followed by its oxidation number in roman numerals within brackets.
• There should be no space in between the name and the brackets.

Based on the above discussion, the systematic name of the given complex compound can be given as $\text{hexaamminecobalt}\left(\text{III}\right)\text{chloride}\text{.}$

(d)

Interpretation Introduction

Interpretation: The systematic names for the given compounds to be predicted.

Concept Introduction:

Systematic naming is the standard name given in a systematic way to a unique complex compound.

Systematic naming for the complex compound can be given based on the few important guidelines given below:

1. 1. The name of the ligand is followed by the name of the central metal cation of a complex compound.
2. 2. If there is more than one type of ligand, then their names are arranged in an alphabetical order.
3. 3. When more than one same type of ligands are present, then the Greek prefixes such as di, tri, tetra, penta, and hexa are used to specify their count such as 1,2,3,4.5 and 6 respectively.
4. 4. The oxidation number of the metal is represented in roman numerals immediately following the metal ion name.
5. 5. If the net charge of the complex ion is -ve, then the central metal name should end with the suffix word –ate. Whereas if the net charge of the complex ion is +ve, then the central metal name should end with the suffix word –um.
6. 6. The isomeric form of a given compound should also be mentioned. cis - means that the compound is in the cis-isomeric form in which the different types of ligands will be placed on the same side to each other. trans - means that the compound is in the trans -isomeric form in which the different types of ligands are placed on the opposite side to each other.
7. 7. The more than one count of the poly-dentate ligands should be specified as bis, tris respective to the count 2 and 3.
8. 8. Poly-dentate ligand means ligands which can donate more than one lone pair of electrons. The various polydentate ligands are as follows:
   1. 1) Mono-dentate ligand: The ligand that can donate one electron pair to the central metal atom.
   2. 2) Bi-dentate ligand: The ligand that can donate two electron pairs to the central metal atom.
   3. 3) Tri-dentate ligand: The ligand that can donate three electron pairs to the central metal atom.
   4. 4) Tetra-dentate ligand: The ligand that can donate four electron pairs to the central metal atom.
   5. 5) Penta-dentate ligand: The ligand that can donate five electron pairs to the central metal atom.

       and so on…

9. 9. The name of the ions outside the co-ordination sphere should be named generally without the need mentioning its count as the prefix name because such ionic species are not considered as ligands. The same has to be followed for naming the counter ions which will be present before the complex.

Answer to Problem 20.16QP

The systematic name of is ${\text{[Co(NH}}_3{\text{)}}_5{\text{Cl]Cl}}_2$$\text{pentaamminechlorocobalt}\left(\text{III}\right)\text{chloride}\text{.}$

Explanation of Solution

• The given compound is ${\text{[Co(NH}}_3{\text{)}}_5{\text{Cl]Cl}}_2$.

${\text{NH}}_{\text{3}}\to \text{named}\text{as}\text{ammine}$. It is a ligand with neutral charge. There are five ${\text{NH}}_{\text{3}}$ ligands. So, the name of the ligand should hold the prefix name as “penta-“.

$\text{Cl}\to \text{named}\text{as}\text{chloro}$. It is a ligand with negative charge -1. There is only one $\text{Cl}$ atom inside the complex, so the name of the ligand can be named generally as it is whereas there are two $\text{Cl}$ ions outside the complex which are not ligands so the name should be given as “chloride”.

• The oxidation state of the central metal cobalt atom can be calculated as follows:

${\text{[Co(NH}}_3{\text{)}}_5{\text{Cl]Cl}}_2$

$\begin{array}{l}\text{Ligand-}\text{Cl}\text{has}\text{the}\text{charge}\text{as}-1.\\ 1\left(\text{Cl}\right)\text{has}\text{the}\text{charge}\text{as}1\times -1=-1\end{array}$

• The two chlorine atoms outside the complex contribute the charge of -2. In order to balance this charge the complex holds the net charge as +2.

$\begin{array}{l}\text{Ligand-}{\text{NH}}_{\text{3}}\text{has}\text{the}\text{charge}\text{as}0.\\ 5\left({\text{NH}}_{\text{3}}\right)\text{has}\text{the}\text{charge}\text{as}5\times 0=0\end{array}$

• The sum of the oxidation states of the ligands and the central metal can be equated to the net charge of the complex ion to obtain the oxidation number of the central metal.
• The net charge of the complex is +2.
• $\text{Let}\text{the}\text{oxidation}\text{number}\text{of}\text{Co}\text{be}{}^{\text{'}}\text{x}{}^{\text{'}}$

$\begin{array}{c}\text{x}+0-1=+2\\ \text{x}=+2+1\\ \therefore \text{The}\text{oxidation}\text{number}\text{of}\text{Co}\text{is}+3\end{array}$

• The names of the two ligands should be alphabetically arranged.
• The name of the metal ion should follow the name of the ligand.
• The name of the central metal ion should be immediately followed by its oxidation number in roman numerals within brackets.
• There should be no space in between the name and the brackets.

Based on the above discussion, the systematic name of the given complex compound can be given as $\text{pentaamminechlorocobalt}\left(\text{III}\right)\text{chloride}\text{.}$

(e)

Interpretation Introduction

Interpretation: The systematic names for the given compounds to be predicted.

Concept Introduction:

Systematic naming is the standard name given in a systematic way to a unique complex compound.

Systematic naming for the complex compound can be given based on the few important guidelines given below:

1. 1. The name of the ligand is followed by the name of the central metal cation of a complex compound.
2. 2. If there is more than one type of ligand, then their names are arranged in an alphabetical order.
3. 3. When more than one same type of ligands are present, then the Greek prefixes such as di, tri, tetra, penta, and hexa are used to specify their count such as 1,2,3,4.5 and 6 respectively.
4. 4. The oxidation number of the metal is represented in roman numerals immediately following the metal ion name.
5. 5. If the net charge of the complex ion is -ve, then the central metal name should end with the suffix word –ate. Whereas if the net charge of the complex ion is +ve, then the central metal name should end with the suffix word –um.
6. 6. The isomeric form of a given compound should also be mentioned. cis - means that the compound is in the cis-isomeric form in which the different types of ligands will be placed on the same side to each other. trans - means that the compound is in the trans -isomeric form in which the different types of ligands are placed on the opposite side to each other.
7. 7. The more than one count of the poly-dentate ligands should be specified as bis, tris respective to the count 2 and 3.
8. 8. Poly-dentate ligand means ligands which can donate more than one lone pair of electrons. The various polydentate ligands are as follows:
   1. 1) Mono-dentate ligand: The ligand that can donate one electron pair to the central metal atom.
   2. 2) Bi-dentate ligand: The ligand that can donate two electron pairs to the central metal atom.
   3. 3) Tri-dentate ligand: The ligand that can donate three electron pairs to the central metal atom.
   4. 4) Tetra-dentate ligand: The ligand that can donate four electron pairs to the central metal atom.
   5. 5) Penta-dentate ligand: The ligand that can donate five electron pairs to the central metal atom.

       and so on…

9. 9. The name of the ions outside the co-ordination sphere should be named generally without the need mentioning its count as the prefix name because such ionic species are not considered as ligands. The same has to be followed for naming the counter ions which will be present before the complex.

Answer to Problem 20.16QP

The systematic name of ${\text{[trans-Pt(NH}}_{\text{3}}{\text{)}}_2{\text{Cl}}_2\text{]}$ is $\text{trans-diamminedichloroplatinum(II)}\text{.}$

Explanation of Solution

• The given compound is ${\text{[trans-Pt(NH}}_{\text{3}}{\text{)}}_2{\text{Cl}}_2\text{]}$.

trans - means that the compound is in the trans -isomeric form in which the different types of ligands are placed on the opposite side to each other.

${\text{NH}}_{\text{3}}\to \text{named}\text{as}\text{ammine}$. It is a ligand with neutral charge. There are two ${\text{NH}}_{\text{3}}$ ligands. So, the name of the ligand should hold the prefix name as “di-“.

$\text{Cl}\to \text{named}\text{as}\text{chloro}$. It is a ligand with negative charge -1. There are two $\text{Cl}$ atoms inside the complex, so the name of the ligand should hold the prefix name as “di-“.

• The oxidation state of the central metal cobalt atom can be calculated as follows:

${\text{[trans-Pt(NH}}_{\text{3}}{\text{)}}_2{\text{Cl}}_2\text{]}$

$\begin{array}{l}\text{Ligand-}\text{Cl}\text{has}\text{the}\text{charge}\text{as}-1.\\ 2\left(\text{Cl}\right)\text{have}\text{the}\text{charge}\text{as}2\times -1=-2\end{array}$

$\begin{array}{l}\text{Ligand-}{\text{NH}}_{\text{3}}\text{has}\text{the}\text{charge}\text{as}0.\\ 2\left({\text{NH}}_{\text{3}}\right)\text{have}\text{the}\text{charge}\text{as}2\times 0=0\end{array}$

• The sum of the oxidation states of the ligands and the central metal can be equated to the net charge of the complex ion to obtain the oxidation number of the central metal.
• The net charge of the complex is 0.
• $\text{Let}\text{the}\text{oxidation}\text{number}\text{of}\text{Pt}\text{be}{}^{\text{'}}\text{x}{}^{\text{'}}$

$\begin{array}{c}\text{x}+0-2=0\\ \text{x}=+2\\ \therefore \text{The}\text{oxidation}\text{number}\text{of}\text{Pt}\text{is}+2\end{array}$

• The names of the two ligands should be alphabetically arranged.
• The name of the metal ion should follow the name of the ligand.
• The name of the central metal ion should be immediately followed by its oxidation number in roman numerals within brackets.
• There should be no space in between the name and the brackets.

Based on the above discussion, the systematic name of the given complex compound can be given as $\text{trans-diamminedichloroplatinum(II)}\text{.}$