Answer to Question #305910 in Organic Chemistry for tuh

Question

Rank the elements by effective nuclear charge, 𝑍eff, for a valence electron.

Answer 1

The effective nuclear charge (often symbolized as Zeff or Z*) is the net positive charge experienced by an electron in a multi-electron atom.

The effective nuclear charge on such an electron is given by the following equation: $Z_{eff}$ = Z – S

where Z is the number of protons in the nucleus (atomic number), and S is the average number of electrons between the nucleus and the given electron (the number of nonvalence electrons).

$Z_{eff}$ (Sb) = 51 – 46 = 5+;

$Z_{eff}$ (Sn) = 50 – 46 = 4+;

$Z_{eff}$ (Sr) = 38 – 36 = 2+;

$Z_{eff}$ (In) = 49 – 46 = 3+;

$Z_{eff}$ (Rb) = 37 – 36 = 1+;

So the rank will be: $Z_{eff}$ (Sb) > $Z_{eff}$ (Sn) > $Z_{eff}$ (In) > $Z_{eff}$ (Sr) > $Z_{eff}$ (Rb)

Answer: $Z_{eff}$ (Sb) > $Z_{eff}$ (Sn) > $Z_{eff}$ (In) > $Z_{eff}$ (Sr) > $Z_{eff}$ (Rb)