If NaCl is doped with mol% GaCl3 , what is the concentration of the cation vacancies per mole of NaCl?
We have,
100 moles of NaCl are doped with moles of .
Thus, 1 mole of NaCl is doped with moles
Now, as we know, that as one Ga3+ ion is introduced, three Na+ needs to be removed to maintain the electrical neutrality. So as one vacancy is filled by Ga3+ ion , two cation vacancies are formed.
Therefore, concentration of cation vacancy moles/mole of NaCl
Thus, the number of Cationic vacancy per mole of NaCl
Hence, concentration of cation vacancies per mole of NaCl
Therefore, Option(2) is correct