Chapter 7, Problem 90A

Interpretation Introduction

Interpretation : The formation of a cation that is an exception to the octet rule is to be described. The electronic configuration of the cation to the electron configuration of the nearest noble gas is to be compared.

Concept Introduction : According to the octet rule, atoms frequently acquire the noble gas's electron configuration. Eight sets are called an octet.

Answer to Problem 90A

Silver is a metal that has exceptions to the octet rule. The silver metal loses one electron and forms a cation. The nearest noble gas of silver is xenon where there is 8 electrons difference between xenon and the formed silver cation.

Explanation of Solution

Metals usually lose electrons to get the octet configuration while non-metals gain electrons.

There are some exceptions to the octet rule in some transition metals.

The electronic configuration of silver is $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{10}4s^{2}4p^{6}4d^{10}5s^1$ .

A silver atom would need to lose eleven electrons to have the configuration of krypton, the preceding noble gas.

Otherwise, silver would need to gain seven electrons to match the electronic configuration of xenon.

These options are incredibly rare because ions with charges of three or higher are uncommon.

As a result, silver is unable to adopt a noble-gas structure.

However, if it loses its $5s^1$ electron, the resulting outer configuration is $4s^{2}4p^{6}4d^{10}$ , which has all of the orbitals filled and 18 electrons in the highest occupied energy level. Such elements are called pseudo-noble gas configurations.

The outer electronic configuration of xenon is $5s^{2}5p^6$ .

There is eight electrons difference between xenon and silver cations.