The first ionization energy of $\mathrm{Mg}, \mathrm{Al}, \mathrm{P}$ and S follows the order

The first ionization energy of $\mathrm{Mg}, \mathrm{Al}, \mathrm{P}$ and S follows the order
  1. $\mathrm{Mg} < \mathrm{Al} < \mathrm{P} < \mathrm{S}$
  2. $\mathrm{Al} < \mathrm{Mg} < \mathrm{P} < \mathrm{S}$
  3. $\mathrm{Al} < \mathrm{Mg} < \mathrm{S} < \mathrm{P}$
  4. $\mathrm{Mg} < \mathrm{Al} < \mathrm{S} < \mathrm{P}$

Solution

In a period, the value of ionization potential increases from left to right with breaks where the atoms have somewhat stable configurations. Due to stable configurations of $\mathrm{Mg}$ and $\mathrm{P}$ in 3 rd period have higher values than expected
$\begin{array}{llll}\text { Element } & P> & S> & M g> & A l \\ \left(I E_{1}ight) & 11.0 & 10.4 & 7.6 & 6.0\end{array}$ ^

Asked in: JEE-TOPICTESTS-CHEMISTRY

Practice more CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIES questions on Aicharya