Question

Element with the lowest and highest I.P values in each period respectively are
(A) alkali metals, noble gases
(B) alkali metals, halogens
(C) Halogens, alkali metals
(D) Noble gases, Alkali metals

Answer 1

Hint: In order to find which element in the period has the lowest and highest Ionization potential, we must first know what an ionization potential is. Ionization potential is defined as the minimum amount of energy required to remove the electron which is very loosely bound from an atom or molecule.

Complete Solution :
Let us first understand about the ionization potential before moving onto the problem. ionization potential is the minimum amount of energy required in order to remove the electron that is loosely bound from an atom or molecule. Ionization potential can also be referred to as the Ionization energy. This is an endothermic process.
- The electrons from the alkali metals can be easily removed because the alkali metals will have only one valence electron, so it will be easy to remove an electron from it easily. Therefore, alkali metals will have low ionization potential as it will require only a minimum energy to remove the electron.
- The electrons present in the noble gases are hard to remove because noble gases will be having a stable configuration, i.e. octet configuration. Therefore, it will require maximum energy to remove an electron from the noble gases. Hence highest ionization potential will be required.
So, the correct answer is “Option A”.

Note: We should remember that Ionization potential is different from the electronegativity and electron affinity. Electronegativity is the ability of an atom present in a molecule to attract the electron pair towards itself. While the electron affinity is the amount of energy released by an atom or molecule when it gains an electron from the outside.