Question
Ionic radii are
A.
inversely proportional to effective nuclear charge
B.
inversely proportional to square of effective nuclear charge
C.
directly proportional to effective nuclear charge
D.
directly proportional to square of effective nuclear charge
Answer :
inversely proportional to effective nuclear charge
Solution :
$${\text{Ionic}}\,{\text{radii}} \propto \frac{1}{{{Z_{eff}}}}$$
$${Z_{eff}} \to $$ effective nuclear charge
This $${{Z_{eff}}}$$ is calculated as follows :
$${Z_{eff}} = Z - $$ screening constant $$\left( \sigma \right)$$
This value of screening constant is based upon the number of electrons in valence shell as well as in penultimate shells.