What is Ionization Energy?

Ionization Energy is defined as the difficulty in removing the electron from an atom or ion.

X + Δ ⟶  X+ + e

Ionization is an endothermic process as the energy needs to be supplied in order to remove the electron. The ionization energy increases as the removal of electrons takes place due to the fact that the atom now gains a +ve charge and the electrons are held more tightly.  Thus it is difficult to remove an electron from a cation.

Ionization energy or ionization potential is measured in electronvolts (eV) or KJ/mol. eV is a preferred unit in physics while kJ/mol is a preferred unit in chemistry as chemistry generally deals with 1 mole of an atom.

Ionization Energy

Ionization energy can be defined as the minimum amount of energy required to remove the valence electron i.e. the most loosely bound electron from an isolated gaseous atom or ion. It is important to note the term isolated gaseous atom as if the atom is not isolated, then the energy required may be more due to the interatomic forces. 

Let’s learn about Ionization Energy in detail in this article.

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