Question

In a hypothetical solid $A{B}_2,9\%$ of the divalent cation $A^{2+}$ is replaced by a trivalent cation such that the electrical neutrality of the crystal is maintained. Then the of cationic vacancies created is

• A. $5\%$
• B. $9\%$
• C. $3\%$
• D. $6\%$

Answer 1

The correct option is C $3\%$

$3$ divalent cations will be replaved by $2$ trivalent cations.
For every $3$ divalent cations one void is created
$\∴\text{For 9 cations, 3 voids are created}$

$\∴\text{\% cationic vacancy = 3\%}$