Chapter 12.4, Problem 1RQ

Interpretation Introduction

Interpretation:

The way in which Lewis structure of a molecule is helpful in determining its molecular shape is to be explained.

Concept introduction:

Lewis structure is a representation of a molecule which shows shared and unshared pair of electrons. It is helpful to determine the shape of a molecule.

Explanation of Solution

Lewis dot structure shows the bonding and non-bonding pair of electrons.

To determine the shape of molecule, the total number of bonding and non-bonding pairs is to be calculated for the central atom. Then these are arranged in a shape so that electron- electron repulsions are minimum.

For example: methane:

Its Lewis dot structure is:

  

It shows carbon has 4 bonding pairs. Thus these pairs are to be arranged to minimize the electronic repulsion. So its shape is tetrahedral as:

  

This way, molecular shape can be drawn with the help of Lewis structures.

Conclusion

Thus, Lewis structure of a molecule is helpful in determining its molecular shape