Question

What is the opposite of ionization energy?

Answer 1

Hint: Ionization energy can be described as the amount of energy needed to remove the most loosely bound electron i.e. electron present in the outermost electron from an isolated gaseous atom of an element in its lowest energy state or also known by ground state to produce a cation is known as ionization potential.

Complete answer:
Ionization potential is an endothermic process which is generally expressed by the term I or I.P. and measured in electron volts. Energy removed to the first electron is called first ionization energy and to remove second electron it is termed as second ionization energy and so on in their respective manner.
From this we come to know that ionization potential is the energy needed to remove an electron from its outermost shell so its opposite would be the amount of energy needed to gain an electron to complete its shell. The term opposite to ionization energy is generally known by the name electron affinity. It is the amount of energy released when an atom accepts an electron to form a negative ion. Higher electron affinity favors the formation of an anion. Those compounds which have a high tendency to donate an electron pair always show high electron affinity.
Thus the term opposite of ionization energy is known as electron affinity.

Note:
Ionization energy and electron affinity both gives us an idea about the reactivity of chemical compounds i.e. which compound is highly reactive and which one is least and it can also be used to determine the strength of chemical bonds.