Question

Which of the following statements is not true regarding ionization energy?

• A. Ionization energy of $L{i}^{+}$ is greater than $B{e}^{+}$
• B. Second ionization energy of $O$ is greater than $N$
• C. Ionization energy of $Ga$ is greater than that of $Al$
• D. None of the above.

Answer 1

The correct option is D None of the above.

A) Due to the noble gas configuration of $L{i}^{+}$ $\left(1s^2\right)$, it has higher ionization energy than $B{e}^{+}$.

B) Due to the half filled configuration of $O^{+}$ $\left(2s^{2}2p^3\right)$, it has higher ionization energy than $N^{+}$.

C) Due to the poor shielding of $3d$ electrons, the ionization energy of $Ga$ is greater than $Al$.

Hence, all the statements are correct.