If \mathrm{NaCl} is doped with 10^{-3} \mathrm{~mol} \% of \mathrm{SrCl}_{2}, what is the concentration of cation vacancies?
If \mathrm{NaCl} is doped with 10^{-3} \mathrm{~mol} \% of \mathrm{SrCl}_{2}, what is the concentration of cation vacancies?

Ans: It is given that \mathrm{NaCl} is doped with 10^{3} \mathrm{~mol} \% of \mathrm{SrCl}_{2}.
This means that 100 \mathrm{~mol} of \mathrm{NaCl} is doped with 10^{3} \mathrm{~mol} of \mathrm{SrCl}_{2},
Therefore, 1 mol of \mathrm{NaCl} is doped with \frac{10^{-3}}{100} \mathrm{~mol} of \mathrm{SrCl}_{2}