Given below are two statements. One is labelled as
Assertion $A$ and the other is labelled as Reason $R$ .
Assertion $A$ : The first ionization enthalpy for oxygen is lower than that of nitrogen.

Question

Reason $R$ : The four electrons in $2 p$ orbitals of oxygen experience more electron-electron repulsion.

In the light of the above statements, choose the correct answer from the options given below.

TestHub · Accepted Answer

Ionization energy of oxygen is less than that of nitrogen because $2 p$ subshell of nitrogen is half filled, and half filled orbitals have some extra stability, so removing electrons from them will be little more difficult.
And In oxygen atom, $2$ of the $four 2 p$ electrons must occupy the same $2 p$ orbital resulting in an increased electron electron-repulsion.

$N = 1 s^{2} 2 s^{2} 2 p^{3}$

$O = 1 s^{2} 2 s^{2} 2 p^{4}$

Chemistry - PERIODIC TABLE Question with Solution | TestHub

Options:

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