Chapter 2, Problem 2E.19E

(a)

Interpretation Introduction

Interpretation:

Bond angle and shape at central atom in ${\text{S}}_2{\text{O}}_{\text{3}}{}^{2-}$ molecule has to be predicted.

Concept Introduction:

Valence Shell Electron Pair Repulsion model predicts shape by inclusion of bond angles and most distant arrangement of atoms that leads to minimum repulsion. The bonded-atom unshared -pair arrangement and bond angle is decided by the table as follows:

$\begin{array}{cccc}\text{Steric number}& \text{Number of lone pairs}& \text{Molecular geometry}& \text{Bond angles}\\ 2& 0& \text{Linear}& 180°\\ 3& \begin{array}{c}0\\ 1\end{array}& \begin{array}{c}\text{Trigonal planar}\\ \text{Bent}\end{array}& 120°\\ 4& \begin{array}{c}0\\ 1\\ 2\end{array}& \begin{array}{c}\text{Tetrahedral}\\ \text{Trigonal pyramidal}\\ \text{Bent}\end{array}& 109.5°\\ 5& \begin{array}{c}0\\ 1\\ 2\\ 3\end{array}& \begin{array}{c}\text{Trigonal Bi-pyramidal}\\ \text{See-Saw}\\ \text{T-shaped}\\ \text{Linear}\end{array}& 90°\text{,120 }°,180°\\ 6& \begin{array}{c}0\\ 1\\ 2\end{array}& \begin{array}{c}\text{Octahedral}\\ \text{Square pyramidal}\\ \text{Square planar}\end{array}& 90°\text{,}180°\end{array}$

(b)

Interpretation Introduction

Interpretation:

Bond angle at central atom for $\left({\text{CH}}_3\right)\text{Be}$ has to be predicted.

Concept Introduction:

Refer to part (a).

(c)

Interpretation Introduction

Interpretation:

Bond angle and shape at central atom in ${\text{BH}}_{\text{2}}{}^{-}$ molecule has to be predicted.

Concept Introduction:

Refer to part (a).

(d)

Interpretation Introduction

Interpretation:

Bond angle and shape at central atom in ${\text{SnCl}}_2$ molecule has to be predicted.

Concept Introduction:

Refer to part (a).