Question

The correct sequence of increasing covalent character is represented by

• A. $LiCl<NaCl<BeC{l}_2$
• B. $BeC{l}_2<LiCl<NaCl$
• C. $NaCl<LiCl<BeC{l}_2$
• D. $BeC{l}_2<NaCl<LiCl$

Answer 1

The correct option is C

$NaCl<LiCl<BeC{l}_2$

For all the compounds, the anion is the same - chloride. The higher the charge density of the cation, the greater its polarizing power. $B{e}^{2+}$ has twice the charge of $L{i}^{+}$ and yet a smaller radius. By far, $BeC{l}_2$ is the most covalent of the given. $L{i}^{+}$ has higher charge density and thus greater polarizing power than $N{a}^{+}$. Hence the order is:

$NaCl<LiCl<BeC{l}_2$