Question

What is ionization energy how does it vary in periods and Groups of modern periodic table what is the reason for the increasing the nuclear size has the glass goes down​

Answer 1

IONIZATION ENERGY: The energy needed to remove an electron from an atom or molecule to infinity.

The ionization energy is the energy required to remove an electron from its orbital around an atom to a point where it is no longer associated with that atom.

The ionization energy of an element increases as one moves across a period in the periodic table because the electrons are held tighter by the higher effective nuclear charge.

The ionization energy of the elements increases as one moves up a given group because the electrons are held in lower-energy orbitals, closer to the nucleus and therefore are more tightly bound (harder to remove).