WBBSEClass XPhysical Science02 Mark2026 Moderate

QQuestion

Explain with an example of a suitable ionic compound that its ions do not obey the octet rule.

Exam-ready answer 02 Mark

Answer

The octet rule is not obeyed by all ions. For example, lithium hydride (LiH) is an ionic compound.

Li → Li⁺ + e⁻

H + e⁻ → H⁻

The Li⁺ and H⁻ ions have only 2 electrons each in their outermost shell and attain a duplet configuration instead of an octet.

Thus, ions of some ionic compounds such as LiH attain a stable duplet configuration and do not obey the octet rule.

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