Chapter 6, Problem 1E

Interpretation Introduction

To determine:

The reason for using other bonding theories in addition to the Lewis model.

Answer to Problem 1E

Solution:

The Lewis model cannot predict all the properties of a molecule or ion.

Explanation of Solution

Lewis structures are the diagrams that show the bonding between the atoms of the molecules and existing lone pairs of electrons. According to this theory, atoms bonded together to attain stability by completing their octet. This theory also known as Octet theory, which had certain limitations; this theory failed to explain the molecules in which the central atom has either less or more than eight electrons in its valence shell after electron sharing, but the molecules are still quite stable like ${\text{BF}}_{\text{5}}{\text{, AlCl}}_{\text{3}}$ . It also failed to explain large number of covalent molecules such as ${\text{PF}}_{\text{5}}{\text{, IF}}_{\text{7}}$ .

Thus, the Lewis model cannot predict all the properties of a molecule or ion and required other bonding theories which can describe bonding and magnetism in certain species.

Conclusion

Hence, the Lewis model cannot predict all the properties of a molecule or ion and required other bonding theories which can describe bonding and magnetism in certain species.