Question

Why is ionization energy positive?

Answer 1

Ionization energy:

• The amount of energy required to eject the last valence electron from the outermost shell of an isolated gaseous atom is called Ionization potential or energy.
• It is always positive.
• To eject an electron from an atom, we need to give some energy to the system and it becomes an endothermic process and the value for the endothermic process is always taken positive,
• In the periodic table, Helium has the highest and Francium has the lowest first ionization energy.