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Question
Which of the following point defects are shown by AgBr(s) crystals?
- Schottky defect
- Frenkel defect
- Metal excess defect
- Metal deficiency defect
Options
A and B
C and D
A and C
B and D
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Solution
A and B
Explanation:
AgBr shows both Schottky and Frenkel defects.
In AgBr, both Ag+ and Br ions are absent from the lattice causing Schottky defect. However, Ag+ ions are mobile so they have a tendency to move aside the lattice and trapped in interstitial site, hence causing Frenkel defect.
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