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Question
Schottky defect is observed in crystals when ______.
Options
some cations move from their lattice site to interstitial sites.
equal number of cations and anions are missing from the lattice.
some lattice sites are occupied by electrons.
some impurity is present in the lattice.
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Solution
Schottky defect is observed in crystals when equal number of cations and anions are missing from the lattice.
Explanation:
| Defect | Definition | Type of solid |
Effect of defect on density of substance |
Structure of crystal (with defect) |
| Schottky defect |
A crystal is said to have Schottky defect if equal number of cations and anions are missing from their normal lattice site there by creating vacancies or holes. |
Ionic solid |
Decreases |  Schottky defect in a crystal |
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