Question

Which substance has the greatest ionic character ?

• A. $C{l}_{2}O$
• B. $NC{l}_3$
• C. $PbC{l}_2$
• D. $BaC{l}_2$

Answer 1

Answer: (D)

(i) Covalent character $\propto \frac{1}{\text{ size of cation }}\propto$ size of anion

(according to Fajan's rule)

(ii) Lower the covalent character, higher will be ionic character.

$C{l}_{2}O$, contains $O^{2-},NC{l}_3$ contains $N^{3-},PbC{l}_2$

contains $P{b}^{2+}$ and $BaC{l}_2$ contains $B{a}^{2+}$.

Hence, the order of covalent character is

$NC{l}_3>C{l}_{2}O>PbC{l}_2>BaC{l}_2$

$\therefore BaC{l}_2$ has the greatest ionic character.