Question
Question: What type of crystal defect is indicated in the diagram below? Na+ Cl– Na+ Cl– Na+ Cl– Cl– <img sr...
What type of crystal defect is indicated in the diagram below?
Na+ Cl– Na+ Cl– Na+ Cl–
Cl– 
Cl– Na+ Na+
Na+ Cl– Cl– Na+ Cl–
Cl– Na+ Cl– Na+ Na+
A
Frenkel defect
B
Schottky defect
C
Interstitial defect
D
Frenkel and Schottky defects
Answer
Schottky defect
Explanation
Solution
When an atom or ion is missing from its normal lattice site, a lattice vacancy is created. This defect is known as Schottky defect . Here equal number of Na+ and Cl– ions are missing from their regular lattice position in the crystal. So it is Schottky defect.