Chapter 12.4, Problem 4RQ

Interpretation Introduction

Interpretation:

The reason for double bonds to be treated as a single bond while determining the structure needs to be explained.

Concept introduction:

According to the VSEPR theory, a molecule acquires a structure in which there are minimum electron-electron repulsions. The shape depends on the total number of bonding and non-bonding electron pairs around the central atom.

Answer to Problem 4RQ

The double bonds are treated as a single bond while determining the structure because electron clouds of double bond produce the same repulsive effect as a single bond on the central atom.

Explanation of Solution

This can be understood by taking an example:

In $\mathrm{C}{\mathrm{O}}_2$ there is a double bond $\mathrm{C}=\mathrm{O}$ . In it, 4 electrons are involved but they are considered as 1 electron pair because the repulsive effect of the double bond is the same as that of a single bond. That’s why $\mathrm{C}{\mathrm{O}}_2$ is linear.

Conclusion

Thus, multiple bonds are considered as a single bond for determining the molecular structure.