Question

Does "shielding effect" effect the size of element radius

Answer 1

Yes, shielding effect affects the size of an atom.

In a multielectron atom, the electrons interacting with the nucleus, and also with each other.

While electrons are attracted towards the positively charged nucleus, they are repelled by the other electrons. Each electron that is to the nucleus is repelled by the electrons that are present in the inner orbitals. The shielding effect occurs due to repulsion experienced by outer electrons by inner electrons .This electron-electron repulsion decreases the attractive force of the protons on the outer electrons.