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प्रश्न
Why is FeO (s) not formed in stoichiometric composition?
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उत्तर
In the crystals of FeO, some of the Fe2+ cations are replaced by Fe3+ ions. Three Fe2+ ions are replaced by two Fe3+ ions to make up for the loss of positive charge. Eventually there would be less amount of metal as compared to stoichiometric proportion.
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संबंधित प्रश्न
Give reasons : In stoichiometric defects, NaCl exhibits Schottky defect and not Frenkel defect.
Defect shown by non-ionic solids 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.
Assertion: Due to Frenkel defect, there is no effect on the density of the crystalline solid.
Reason: In Frenkel defect, no cation or anion leaves the crystal.
Silver halides generally show:
What is the effect of Frenkel defect on the density of ionic solids?
Cations are present in the interstitial sites in ______.
Schottky defect is observed in crystals when ______.
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.
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. |
Schottky defect is noticed in ______
Which type of ‘defect’ has the presence of cations in the interstitial sites?
