Chapter 9, Problem 9.150MP

Interpretation Introduction

(a)

Interpretation:

The hybridization and geometry around each sulfur atom in ${\text{S}}_8$ 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 that exist on each bonded atom.

Lewis dot structure is also known as Lewis dot formula or electron dot structure. The bond formation between the atoms takes place due to the sharing of valence electrons of bonded atoms while the remaining electrons present in outer shell represented as lone pair of electrons. To draw the Lewis structure, calculate the total number of valence electrons in each atom and draw the structure in such a way that each atom gets its octet configuration

Interpretation Introduction

(b)

Interpretation:

The double bond energy in S=S in ${\text{S}}_{\text{2}\left(\text{g}\right)}$ needs to be determined with the help of $\Delta \text{H°}$ for the reaction given and average S-S bond dissociation energy in 225 kJ/mol.

${\text{S}}_{8\left(\text{g}\right)}\stackrel{}{\to }{\text{4 S}}_{\text{2}\left(\text{g}\right)}\Delta \text{H}°\text{=+237kJ}$

Concept introduction:

The Gibb’s equation of thermodynamic purposed a relation between $\text{ΔS}$, $\text{ΔH}$ and $\text{ΔG}$ with temperature. With the help of this equation the change in $\text{ΔS}$, $\text{ΔH}$ and $\text{ΔG}$ can be predicted. For any reaction the $\text{ΔH}$ and $\text{ΔS}$ can be calculated with the help of:

$\begin{array}{l}\text{ΔrS°= }\Sigma \text{ΔrS°product - }\sum \text{ΔrS°reactant}\\ \text{ΔrH°= }\Sigma \text{ΔrH°product - }\sum \text{ΔrH°reactant}\end{array}$

Interpretation Introduction

(c)

Interpretation:

Molecular orbital description of the bonding in S₂ and whether S₂ is paramagnetic or diamagnetic in nature needs to be determined.

Concept introduction:

The molecular orbital theory explained the bonding, magnetic and spectral properties of a molecule. It is based on the formation of molecular orbitals by the combination of atomic orbitals. On the basis of energy and stability these molecular orbitals can be further classified into three types:

• Bonding molecular orbitals (BMO): They have lesser energy than atomic orbital, therefore, more stable compare to atomic orbital.
• Antibonding molecular orbitals (ABMO): They have higher energy than atomic orbital therefore less stable compare to atomic orbital.
• Non-bonding molecular orbitals (NBMO): They have the same energy as atomic orbital.

A molecular orbital diagram represents the distribution of electrons in different molecular orbitals in increasing order of their energy. Hence lower energy molecular orbitals occupy first then only electron moves in higher energy orbitals.