Advertisements
Advertisements
प्रश्न
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?
Advertisements
उत्तर
(i) Schottky defect is shown by the mentioned crystal, as equal number of cations and anions are missing in the crystal lattice.
(ii) This defect leads to decrease in density, as equal number of the cations and anions are missing from the crystal lattice.
(iii) This kind of defect is shown by those ionic substance in which the cations and anions are of almost similar sizes.
Examples: NaCl, KCl and CsCl.
APPEARS IN
संबंधित प्रश्न
Give reasons : In stoichiometric defects, NaCl exhibits Schottky defect and not Frenkel defect.
non-stoichiometric defects?
Answer the following question.
What type of stoichiometric defect is shown by ZnS and why?
Dislocation defect is also known as ____________.
Frenkel defects are not found in alkali metal halides because ____________.
Type of stoichiometric defect shown by ZnS is ____________.
Schottky defect is observed in crystals when ______.
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. |
Given below are two statements, one is labelled as Assertion (A) and the other is labelled as Reason (R):
Assertion: In any ionic solid (MX) with Schottky defects, the number of positive and negative ions are same.
Reason: Equal number of cation and anion vacancies are present.
Which type of ‘defect’ has the presence of cations in the interstitial sites?
