Question

Which of the following shows biggest jump in II and III ionization energy:

• A. 1$s^2$ 2$s^2$ 2$p^6$ 3$s^2$
• B. 1$s^2$ 2$s^2$ 2$p^6$ 3$s^2$, 3$p^2$
• C. 1$s^2$ 2$s^2$ 2$p^6$ 3$s^2$3$p^6$ , 4$s^2$4$p^2$
• D. 1$s^2$ 2$s^2$

Answer 1

The correct option is A

1$s^2$ 2$s^2$ 2$p^6$ 3$s^2$

What do we mean by the biggest jump in II and III ionization energy?

It means a that a relatively larger amount of energy is required to remove the 3rd electron as compared to the 2nd electron one after the other.

$\Rightarrow$ It indirectly implies that after IE(II) or after removing two electrons, the atom should be very stable. If the atom is stable, then we have to provide large amount of energy to remove the next electron.

$\to$ Also, we know that the atom becomes most stable when it acquires noble gas configuration.

$\Rightarrow$ So, in this case, after removing 2 electrons, it should achieve noble gas configuration.

1$s^2$ 2$s^2$ 2$p^6$ 3$s^2$ $\Rightarrow$(after removal of 2 electrons) 1$s^2$ 2$s^2$ 2$p^6$ (Ne configuration)

Therefore, the biggest jump in II and III ionization energy is in 1$s^2$ 2$s^2$ 2$p^6$ 3$s^2$