Chapter 12.4, Problem 5RQ

(a)

Interpretation Introduction

Interpretation:

The molecular structure of ${\mathrm{H}}_2\mathrm{S}$ is to be predicted.

Concept introduction:

The molecular structure can be determined by drawing Lewis structure and then counting total bond pairs and lone pairs and assigning the structure according to VSEPR theory.

Answer to Problem 5RQ

Molecular structure-Bent

Geometry-Tetrahedral

Explanation of Solution

Lewis structure of ${\mathrm{H}}_2\mathrm{S}$ is:

  

Structure shows that in ${\mathrm{H}}_2\mathrm{S}$ central atom sulphur has two bond pairs and two lone pairs. In total it has 4 pairs of electrons. Thus, its geometry is tetrahedral. But due to presence of lone pair of electrons its structure gets distorted and its shape is bent or V-shaped.

(b)

Interpretation Introduction

Interpretation:

The molecular structure of $\mathrm{N}{\mathrm{F}}_3$ is to be predicted.

Concept introduction:

The molecular structure can be determined by drawing Lewis structure and then counting total bond pairs and lone pairs and assigning the structure according to VSEPR theory.

Answer to Problem 5RQ

Molecular structure-Pyramidal

Geometry-Tetrahedral

Explanation of Solution

Lewis structure of $\mathrm{N}{\mathrm{F}}_3$ is:

  

Structure shows that in $\mathrm{N}{\mathrm{F}}_3$ central atom nitrogen has three bond pairs and one lone pair. In total it has 4 pairs of electrons. Thus, its geometry is tetrahedral. But due to presence of lone pair of electrons its structure gets distorted and its shape is pyramidal.

(c)

Interpretation Introduction

Interpretation:

The molecular structure of $\mathrm{C}{\mathrm{O}}_3{}^{2-}$ ion is to be predicted.

Concept introduction:

The molecular structure can be determined by drawing Lewis structure and then counting total bond pairs and lone pairs and assigning the structure according to VSEPR theory

Answer to Problem 5RQ

Molecular structure- Trigonal planar

Geometry-Trigonal planar

Explanation of Solution

Lewis structure of $\mathrm{C}{\mathrm{O}}_3{}^{2-}$ is:

  

Structure shows that in $\mathrm{C}{\mathrm{O}}_3{}^{2-}$ central atom carbon has three bond pairs and no lone pair. In total it has 3 pairs of electrons. Thus, its geometry is trigonal planar.

(d)

Interpretation Introduction

Interpretation:

The molecular structure of $\mathrm{S}\mathrm{i}{\mathrm{F}}_4$ molecule is to be predicted.

Concept introduction:

The molecular structure can be determined by drawing Lewis structure and then counting total bond pairs and lone pairs and assigning the structure according to VSEPR theory

Answer to Problem 5RQ

Molecular structure- Tetrahedral

Geometry-Tetrahedral

Explanation of Solution

Lewis structure of $\mathrm{S}\mathrm{i}{\mathrm{F}}_4$ is:

  

Structure shows that in $\mathrm{S}\mathrm{i}{\mathrm{F}}_4$ central atom silicon has four bond pairs and no lone pairs. In total it has 4 pairs of electrons. Thus, its geometry is tetrahedral.