Chapter 9.1, Problem 1PPB

Interpretation Introduction

Interpretation:

The groups to which the terminal atoms in a ${\text{AB}}_x$ molecule belongs, is to determined.

Concept Introduction:

In a Lewis structure of a molecule, generally, the element with a smaller number of atoms is the central atom, and the other atoms are the terminal atoms. When more than two types of elements are present, then the less electronegative element is the central atom.

To draw a Lewis structure, first the sum of valence electrons of all the atoms is determined.

A skeleton structure is drawn, connecting all the atoms. Each bond contains of two electrons.

Then the electrons are placed on the terminal atoms as lone pairs, so as to complete their octet.

The remaining electrons are placed around the central atom as lone pairs.

If there isno valence electrons to complete the octet of the central atom, then one or more terminal atoms share a lone pair to form a double bond.

Electron domain is the bond pair and lone pair of electrons around the central atom.

According to VSEPR model, the electron domain arranges itself as far as possible to minimize repulsions between the electrons.

Molecular geometry is the spatial arrangement of bonded atoms. If no lone pairs of electrons are present, then molecular geometry is identical to the electron domain geometry.

The repulsion between the lone pair-lone pair is greater than in lone pair-bond pair, which in turn is greater than in a bond pair-bond pair.