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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
What type of defect is shown by NaCl in
stoichiometric defects, and
Out of NaCl and AgCl, which one shows Frenkel defect and why?
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 ____________.
The radius of Cs+ is 169 pm and Cl− is 181 pm. The radius ratio is ____________.
Type of stoichiometric defect shown by AgBr is ____________.
The following diagram shows:
Which is not correct about the Schottky defects?
Alkali halids do not show Frenkel defect because ____________.
Which of the following crystals does not exhibit Frenkel defect?
Silver halides generally show:
In a Schottky defect ____________.
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 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?
Match the defects given in Column I with the statements in given Column II.
| Column I | Column II |
| (i) Simple vacancy defect | (a) shown by non-ionic solids and increases density of the solid. |
| (ii) Simple interstitial defect | (b) shown by ionic solids and decreases density of the solid. |
| (iii) Frenkel defect | (c) shown by non ionic solids and density of the solid decreases. |
| (iv) Schottky defect | (d) shown by ionic solids and density of the solid remains the same. |
