The shielding of electrons gives rise to an effective nuclear charge, Z_eff, which explains why boron is larger than oxygen. Estimate the approximate Z_eff felt by a valence electron of boron and oxygen, respectively?

Calculate Z_eff for a 3d electron in a copper atom, Cu.

Rank the following elements by effective nuclear charge, Z_Eff, for a valence electron: Kr, Se, Ca, K, Ge

Which will experience the greater effective nuclear charge, the electrons in the 𝑛=3 shell in Ar or the 𝑛=3 shell in Kr? Which is more likely to be closer to the nucleus?

Arrange the following atoms in order of increasing effective nuclear charge experienced by the electrons in the 𝑛=3 electron shell: K, Mg, P, Rh, Ti.