Chapter 14, Problem 29E

(a)

Interpretation Introduction

Interpretation: The number of carbon atoms with ${\text{sp}}^{\text{3}}$ hybridization in AZT molecule needs to be determined.

  

Concept Introduction:

Lewis dot structure is the representation which shows the bonding between atoms present in a molecule. It shows lone pairs and bond pairs existing on each bonded atom. Lewis dot structure is also known as Lewis dot formula or electron dot structure.

The sum of valence electrons must be arranged in such a way that all atoms must get octet configuration (8 electrons).

  $\text{Hybridization = Number of sigma bonds + Number of lone pairs on bonded atoms}\text{.}$

Answer to Problem 29E

There are 6 carbon atoms in ${\text{sp}}^{\text{3}}$ hybridization in AZT molecule.

Explanation of Solution

A ${\text{sp}}^{\text{3}}$ hybridize carbon atom must have all the sigma bonds with other atoms as from the hybridization formula;

  $\begin{array}{l}\text{Hybridization = Number of sigma bonds + Number of lone pairs on bonded atoms}\text{.}\\ {\text{Hybridization = 4 + 0 or 3 +1 = 4 = sp}}^{\text{3}}\end{array}$

  

All the asterisk C atoms are ${\text{sp}}^{\text{3}}$ hybridized carbon atoms in the molecule.

(b)

Interpretation Introduction

Interpretation: The number of carbon atoms with ${\text{sp}}^2$ hybridization in AZT molecule needs to be determined.

  

Concept Introduction:

Lewis dot structure is the representation which shows the bonding between atoms present in a molecule. It shows lone pairs and bond pairs existing on each bonded atom. Lewis dot structure is also known as Lewis dot formula or electron dot structure.

The sum of valence electrons must be arranged in such a way that all atoms must get octet configuration (8 electrons).

  $\text{Hybridization = Number of sigma bonds + Number of lone pairs on bonded atoms}\text{.}$

Answer to Problem 29E

There are 4 carbon atoms in ${\text{sp}}^2$ hybridization in AZT molecule.

Explanation of Solution

A ${\text{sp}}^2$ hybridize carbon atom must have one pi bond at least with other atoms as from the hybridization formula;

  $\begin{array}{l}\text{Hybridization = Number of sigma bonds + Number of lone pairs on bonded atoms}\text{.}\\ {\text{Hybridization = 3 + 0 or 2 +1 = 3 = sp}}^{\text{2}}\end{array}$

  

All the asterisk C atoms are ${\text{sp}}^2$ hybridized carbon atoms in the molecule.

(c)

Interpretation Introduction

Interpretation: The number of carbon atoms with $\text{sp}$ hybridization in AZT molecule needs to be determined.

  

Concept Introduction:

Lewis dot structure is the representation which shows the bonding between atoms present in a molecule. It shows lone pairs and bond pairs existing on each bonded atom. Lewis dot structure is also known as Lewis dot formula or electron dot structure.

The sum of valence electrons must be arranged in such a way that all atoms must get octet configuration (8 electrons).

  $\text{Hybridization = Number of sigma bonds + Number of lone pairs on bonded atoms}\text{.}$

Answer to Problem 29E

The N atoms which forms two double covalent bond is sp-hybridized only.

Explanation of Solution

A $\text{sp}$ hybridize carbon atom must have 2 pi bond or one triple covalent bond with other atoms as from the hybridization formula;

  $\begin{array}{l}\text{Hybridization = Number of sigma bonds + Number of lone pairs on bonded atoms}\text{.}\\ {\text{Hybridization = 3 + 0 or 2 +1 = 3 = sp}}^{\text{2}}\end{array}$

There is no $\text{sp}$ hybridized carbon atoms in the molecule as all C atoms are either single bonded or double bonded carbon atoms. The N atoms which forms two double covalent bond is sp-hybridized only.

(d)

Interpretation Introduction

Interpretation: The number of σ-bonds in AZT molecule needs to be determined.

  

Concept Introduction:

Lewis dot structure is the representation which shows the bonding between atoms present in a molecule. It shows lone pairs and bond pairs existing on each bonded atom. Lewis dot structure is also known as Lewis dot formula or electron dot structure.

The sum of valence electrons must be arranged in such a way that all atoms must get octet configuration (8 electrons).

  $\text{Hybridization = Number of sigma bonds + Number of lone pairs on bonded atoms}\text{.}$

Answer to Problem 29E

The total number of σ bonds are 33 in AZT molecule

Explanation of Solution

There are two types of covalent bonds; σ bond and π-bonds. A σ-bond is formed by head-to head overlapping of hybridized orbitals. It is a strong bond and can exist between two bonded atoms. On the contrary, a π-bond is a weak covalent bond as it forms by side-way-overlapping of un-hybridized orbitals.

Since it is a weak bond therefore it is always exist with σ-bond in a double and triple covalent bond. A double covalent bond is formed by 1σ and 1 π bond whereas a triple covalent bond is formed by 1σ and two π bonds. In the given molecule, all single bonds are σ-bonds and all double bonds have 1 σ bonds. Therefore total number of σ bonds are 33 in AZT molecule.

(e)

Interpretation Introduction

Interpretation: The number of π-bonds in AZT molecule needs to be determined.

  

Concept Introduction:

Lewis dot structure is the representation which shows the bonding between atoms present in a molecule. It shows lone pairs and bond pairs existing on each bonded atom. Lewis dot structure is also known as Lewis dot formula or electron dot structure.

The sum of valence electrons must be arranged in such a way that all atoms must get octet configuration (8 electrons).

  $\text{Hybridization = Number of sigma bonds + Number of lone pairs on bonded atoms}\text{.}$

Answer to Problem 29E

The total number of π bonds are 5 in AZT molecule

Explanation of Solution

There are two types of covalent bonds; σ bond and π-bonds. A σ-bond is formed by head-to head overlapping of hybridized orbitals. It is a strong bond and can exist between two bonded atoms. On the contrary, a π-bond is a weak covalent bond as it forms by side-way-overlapping of un-hybridized orbitals.

Since it is a weak bond therefore it is always exist with σ-bond in a double and triple covalent bond. A double covalent bond is formed by 1σ and 1 π bond whereas a triple covalent bond is formed by 1σ and two π bonds. In the given molecule, total number of π bonds are 5 in AZT molecule.

(f)

Interpretation Introduction

Interpretation: The bond angle in the N-N-N (azide group) of AZT molecule needs to be determined.

  

Concept Introduction:

Lewis dot structure is the representation which shows the bonding between atoms present in a molecule. It shows lone pairs and bond pairs existing on each bonded atom. Lewis dot structure is also known as Lewis dot formula or electron dot structure.

The sum of valence electrons must be arranged in such a way that all atoms must get octet configuration (8 electrons).

  $\text{Hybridization = Number of sigma bonds + Number of lone pairs on bonded atoms}\text{.}$

Answer to Problem 29E

With sp-hybridization, the bond angle must be 180°.

Explanation of Solution

Hybridization of central N atom in azide group is:

  $\begin{array}{l}\text{Hybridization = Number of sigma bonds + Number of lone pairs on bonded atoms}\text{.}\\ \text{Hybridization = 2+ 0 = 2 = sp}\end{array}$

With sp-hybridization, the bond angle must be 180°.

(g)

Interpretation Introduction

Interpretation: The bond angle in the H-O-C in the side group attached to the five membered ring of AZT molecule needs to be determined.

  

Concept Introduction:

Lewis dot structure is the representation which shows the bonding between atoms present in a molecule. It shows lone pairs and bond pairs existing on each bonded atom. Lewis dot structure is also known as Lewis dot formula or electron dot structure.

The sum of valence electrons must be arranged in such a way that all atoms must get octet configuration (8 electrons).

  $\text{Hybridization = Number of sigma bonds + Number of lone pairs on bonded atoms}\text{.}$

Answer to Problem 29E

With ${\text{sp}}^{\text{3}}$ -hybridization, the bond angle must be 109°.

Explanation of Solution

Hybridization of central C atom in −CH₂OH group attached to the five membered ring:

  $\begin{array}{l}\text{Hybridization = Number of sigma bonds + Number of lone pairs on bonded atoms}\text{.}\\ {\text{Hybridization = 4+ 0 = 4 = sp}}^{\text{3}}\end{array}$

With ${\text{sp}}^{\text{3}}$ -hybridization, the bond angle must be 109°.

(h)

Interpretation Introduction

Interpretation: The hybridization of O atom in −CH₂OH group attached to the five membered ring of AZT molecule needs to be determined.

  

Concept Introduction:

Lewis dot structure is the representation which shows the bonding between atoms present in a molecule. It shows lone pairs and bond pairs existing on each bonded atom. Lewis dot structure is also known as Lewis dot formula or electron dot structure.

The sum of valence electrons must be arranged in such a way that all atoms must get octet configuration (8 electrons).

  $\text{Hybridization = Number of sigma bonds + Number of lone pairs on bonded atoms}\text{.}$

Answer to Problem 29E

The hybridization of O atom in −CH₂OH group attached to the five membered ring is ${\text{sp}}^{\text{3}}$ .

Explanation of Solution

Hybridization of O atom in −CH₂OH group attached to the five membered ring:

  $\begin{array}{l}\text{Hybridization = Number of sigma bonds + Number of lone pairs on bonded atoms}\text{.}\\ {\text{Hybridization = 2+ 2 = 4 = sp}}^{\text{3}}\end{array}$

The hybridization of O atom in −CH₂OH group attached to the five membered ring is ${\text{sp}}^{\text{3}}$ .