In multielectron atoms many of the periodic trends can be explained in terms of Z_eff. Consider the following statements and discuss whether or not the statement is true or false.

(a) Electrons in a p orbital are more effective than electrons in the s orbitals in shielding other electrons from the nuclear charge.

(b) Z_eff for an electron in an s orbital is lower than that for an electron in a p orbital in the same shell.

(c) Z_eff is usually less than Z.

(d) Electrons in orbitals having ℓ = 1 penetrate better than those with ℓ =2.

(e) Z_eff for the orbitals of the elements Na(3s), Mg(3s), Al(3p), P(3p), and S(3p) are in the order Z_eff(Na) < Z_eff(Mg) > Z_eff(Al) < Z_eff(P) > Z_eff(S).