For $\mathrm{NaCl}$, the number of Schottky pairs per $\mathrm{cm}^3$ at room temperature is
For $\mathrm{NaCl}$, the number of Schottky pairs per $\mathrm{cm}^3$ at room temperature is
$10^{12}$
$10^{23}$
$10^{6}$
$10^{4}$
Solution
For $1 \mathrm{~cm}^3$ of $\mathrm{NaCl}$, there are $10^{22}$ ions, so there are $10^{16}$ ions present per Schottky defect.
Therefore, for each $\mathrm{cm}^3$, there are $10^6$ Schottky pairs at room temperature.