JEE Mains Model Paper 10

1 mole of NaCl is doped with SrCl2 =

10−3

100

mole = 10−5 mole
As each Sr+2 ion introduced one cation vacancy,
Concentration of cation vacancies = 10–5 mole/mole of NaCl
= 10–5 × 6.023 × 1023 mol–1 of NaCl = 6.023 × 1018mol–1