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प्रश्न
Schottky defect is observed in crystals when ______.
विकल्प
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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उत्तर
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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संबंधित प्रश्न
Give reasons : In stoichiometric defects, NaCl exhibits Schottky defect and not Frenkel defect.
Examine the given defective crystal:
Answer the following questions :
(i) What type of stoichiometric defect is shown by the crystal?
(ii) How is the density of the crystal affected by this defect?
(iii) What type of ionic substances show such defect?
Answer the following question.
What type of stoichiometric defect is shown by ZnS and why?
Ionic solids containing large differences in sizes of ions show ____________.
Point defect is also known as ____________.
Dislocation defect is also known as ____________.
Frenkel defects are not found in alkali metal halides because ____________.
Type of stoichiometric defect shown by ZnS is ____________.
Type of stoichiometric defect shown by AgBr is ____________.
Which is not correct about the Schottky defects?
Assertion: No compound has both Schottky and Frenkel defects.
Reason: Both defects change the density of the solid.
Cations are present in the interstitial sites in ______.
Which of the following point defects are shown by AgBr(s) crystals?
- Schottky defect
- Frenkel defect
- Metal excess defect
- Metal deficiency defect
Which of the following defects is also known as dislocation defect?
Which of the following statements are not true?
(i) Vacancy defect results in a decrease in the density of the substance.
(ii) Interstitial defects results in an increase in the density of the substance.
(iii) Impurity defect has no effect on the density of the substance.
(iv) Frankel defect results in an increase in the density of the substance.
Why is FeO (s) not formed in stoichiometric composition?
If NaCl is doped with 10–4 mole percent of SrCl2 the concentration of cation vacancies will be
The incorrect statement about the imperfections in solids is ______.
