Ionization Energy. The ionization energy tends to increase as one moves from left to right across a given period or up a group in the periodic table.

Moving Across the Periodic Table. an increase in atomic size because of additional repulsions between electrons, a decrease in size because of the additional protons in the nucleus, no effect at all as the two opposing tendencies of electron repulsion and nuclear attraction balance each other out.

The more shielding, the further the valence shell can spread out and the bigger atoms will be. The effective nuclear charge is the net positive charge experienced by valence electrons. It can be approximated by the equation: Zeff = Z – S, where Z is the atomic number and S is the number of shielding electrons.

The only way for ionization energy to increase across a period is if the only the number of protons and valence electrons have effect on the amount of energy required, not the shielding electrons. So the shielding-effect must stay the same all throughout a period.

If the electron is in s orbital, it means it is nearest to nucleus and if in f shell, it means it is farthest from nucleus. Since, atomic shielding depends on electron density in a orbital and electron density is very less for d and f orbitals, hence it has poor shielding effect as compared to s and p orbitals.

rubidium

s orbital

Shielding is caused by the combination of partial neutralization of nuclear charge by core electrons, and by electron-electron repulsion. The amount of charge felt by an electron depends on its distance from the nucleus.

It has only one orbital and single electron. So, shielding effect is not possible.

Complete Step By Step Answer: Screening effect which is also known as shielding effect that refers to atomic shielding or electron shielding. As it also has only one electron in its shell so screening effect will not be observed in Li2+ .

Bromine is a chemical element with symbol Br and atomic number 35. Classified as a halogen, Bromine is a liquid at room temperature.