Chapter 7.2, Problem 8PP

Interpretation Introduction

Interpretation:

The formation of ionic compound from elements Lithium and oxygen needs to be explained.

Concept introduction:

Chemical compounds are formed when the atoms, ions or molecules of two substances are attracted towards each other forming a chemical bond. This bond can be electrostatic when two oppositely charged ions are attracted towards each other and this bond is said to be ionic bond.

Answer to Problem 8PP

2 Lithium atoms will lose 2 electrons which is gained by Oxygen to form ionic compound.

Explanation of Solution

The formation of Lithium oxide takes place when Lithium atoms interact with oxygen atom.

The electronic configuration of Lithium is ${\text{1s}}^2{\text{ 2s}}^1$ or $\left[\text{He}\right]{\text{2s}}^1$

Lithium atom has one outermost electron which can be lost to become a positive ion.

Figure 1

The electronic configuration of Oxygen is ${\text{1s}}^2{\text{ 2s}}^2{\text{ 2p}}_{\text{x}}{}^2{\text{ 2p}}_{\text{y}}{}^1{\text{ 2p}}_{\text{z}}{}^1$

Oxygen atom has 2 half filled shells of p orbital. To fill up the half filled shells, it can take up 2 electrons to become a oxide anion.

Figure 2

The 2 electrons can be supplied from 2 of Lithium atoms.

Hence, we can say that 2 Lithium atoms will lose 2 electrons that is gained by Oxygen to get an octet structure and form ionic compound.

The overall compound formed is ${\text{Li}}_2\text{O}$

Conclusion

2 Lithium atoms will lose 2 electrons which is gained by Oxygen to form ionic compound, ${\text{Li}}_2\text{O}$.