The correct order of first ionisation enthalpy is :
Solution
$\matrix{
{Mg} & {Al} & P & {S \to IE} \cr
}$ order $\Rightarrow$ Al < Mg < S < P<br><br>Valence [N<sub>e</sub>] : $$\matrix{
{\mathop {3{s^2}}\limits^{Mg} } & {\mathop {3{s^2}3{P^1}}\limits^{Al} } & {\mathop {3{s^2}3{P^3}}\limits^P } & {\mathop {3{s^2}3{P^4}}\limits^S } \cr
} $$
About this question
Subject: Chemistry · Chapter: Periodic Table and Periodicity · Topic: Periodic Trends
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