Question

Consider the following statements.
1. The IE (I) of nitrogen atom is more than IE (I) of oxygen atom.
2. Electron affinity of oxygen is less than sulphur atom.
3. Electronegativity of an atom has no relation with its ionization enthalpy and electron gain enthalpy
Which of the above statements are correct?
A 1
B 1, 2
C 2, 3
D 1, 2 and 3

Answer 1

Ionization energy is the minimum energy required to remove the outermost electron that is loosely bound to the atom and electron affinity is the energy change that occurs while adding an electron to a gaseous atom.

Complete step by step answer:
The minimum energy required to remove the loosely bound electrons from the outermost orbit of an isolated neutral gaseous atom is called ionization energy.
Nitrogen has an electronic configuration of ${\text{1}}{{\text{s}}^{\text{2}}}{\text{2}}{{\text{s}}^{\text{2}}}{\text{2}}{{\text{p}}^{\text{3}}}$
Oxygen has an electronic configuration of ${\text{1}}{{\text{s}}^{\text{2}}}{\text{2}}{{\text{s}}^{\text{2}}}{\text{2}}{{\text{p}}^{\text{4}}}$
Because of the half-filled configuration of Nitrogen when compared to oxygen which has one electron more than half filled configuration. Nitrogen atoms have more ionization energy when compared to oxygen atoms.
The amount of energy released with the addition of an electron to the neutral atom is called electron affinity. Oxygen is smaller in size and the valence electrons are placed more closely and thus the inter electronic repulsion will be greater and the energy released during addition of an electron is lesser whereas Sulphur is larger in size when compared to oxygen and the energy released during the addition of electron is greater, thus electron affinity of oxygen is less than sulphur atom. If the ionization enthalpy is lesser, it means that it readily donates electrons for the reaction which says that it is less electronegative.

So, the correct answer is Option B.

Additional information:
Electron gain enthalpy is defined as the ability of an atom to attract the outside electrons towards it and electronegativity is the ability of an atom to attract a shared pair of electrons towards itself.

Note: If an atom has got higher electronegativity than the energy required to remove the outermost electrons is greater i.e., ionization energy is higher and if the atom has less electronegativity than the energy required to remove the outermost electrons is less i.e., ionization energy is less.