what are the factors that affect ionisation energy?

Question

sheilding
atomic radius and other things affect the ionisation energy of elements can you please give me detail on how exactly they all affect it.

Answer 1

Factors that influence Ionization energy are:
1.Size of the atom.
2.The charge on the nucleus.
3.How effectively the inner electron shells screen the nuclear charge.
4.The type of electron involved(s,p,d or f)

Shielding and screening are one and the same.

In a small atom the electrons are tightly held, whilst in a larger atom the electrons are less strongly held. thus the ionization energy decreases as the size of the atoms increases.

Answer 2

Ionization energy is the energy necessary to withdraw an electron from an atom and get it away to infinity.

Hence, the variation in atomic radius affects this parameter because the lesser the distance between electron and nucleus within atom, the greater the ionization energy of this electron (you need more energy to disjoint the electron due to electrostac force that attracts the electron to positive charge in nucleus).

That's what I can remember from Chemistry courses.

Good luck!