Question

Which has larger (IE) in each pair?
(a) N or $O^{+}$
(b) ${Be}^{+}$ or $B^{+}$
(c) Be or B
(d) ${Na}^{+}$ or Ne
Give your answer as a 4-digit number, example - 1212/2122 and so on, (1 for first element and 2 for second)

Answer 1

(a) N and $O^{+}$ are isoelectronic species.
But the effective nuclear charge of $O^{+}$ is higher than that of N.
Hence, The correct order of the ionization potential is $N<O^{+}$
(b) The correct order of ionization energy is $B{e}^{+}<B^{+}$. hen an electron is removed from $B{e}^{+}$
stable He electronic configuration is obtained.
When an electron i removed from $B^{+}$, stable $2s^2$ electronic
configuration is broken.
(c) The correct order of ionization energy is $Be>B$
When an electron is removed from Be, stable $2s^2$ electronic configuration is broken
whereas an electron is removed from B, stable $2s^2$ electronic configuration is obtained.
(d) The correct order of ionization energy is $N{a}^{+}>Ne$
Both are isoelectronic species.
$N{a}^{+}$ has higher effective nuclear charge and hence higher ionization energy.
Hence, the correct answer is 2211