Chapter 5, Problem 5.23CP

(a)

Interpretation Introduction

Interpretation:

The geometry around each carbon in thalidomide has to be given.

Concept introduction:

• Molecular geometry is the spatial arrangement of atoms in a molecule. It is the three dimensional arrangement of bonded atoms. Many chemical, physical and even biological properties depend on molecular geometry.
• Using VSEPR theory and Lewis structure, the exact geometry of a molecule can be obtained.
• In VSEPR, the geometry of the molecule is explained based on minimizing electrostatic repulsion between the molecules’ valence electrons around a central atom
• Bond angle is the angle between two bonds of a molecule and it is determined based on the electron-domain geometry.

  [Bond angles: tetrahedral = $\text{109}{\text{.5}}^{\text{o}}$, trigonal planar = ${\text{120}}^{\text{o}}$, T-shape = ${\text{90}}^{\text{o}}$]

Steric number: The number of atoms bonded to the atom+the number of lone pairs the atom has.

Atom will be ${\text{sp}}^{\text{3}}$ hybridized, if the steric number is 4.

Atom will be ${\text{sp}}^2$ hybridized, if the steric number is 3.

Atom will be $\text{sp }$ hybridized, if the steric number is 2.

(b)

Interpretation Introduction

Interpretation:

The hybridization of each carbon of the given thalidomide has to be determined.

Concept introduction:

Hybridization is the mixing of valence atomic orbitals to get equivalent hybridized orbitals that having similar characteristics and energy.

• Geometry of a molecule can be predicted by knowing its hybridization.

Steric number: The number of atoms bonded to the atom+the number of lone pairs the atom has.

Atom will be ${\text{sp}}^{\text{3}}$ hybridized, if the steric number is 4.

Atom will be ${\text{sp}}^2$ hybridized, if the steric number is 3.

Atom will be $\text{sp }$ hybridized, if the steric number is 2.