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Question
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.
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Solution
(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.
Explanation:
(iii) Impurity defect changes the density of substance as impurity has different than the ion present on perfect crystal e.g., When SrCl2 is added to the NaCl crystal, it causes impurity defect.
(iv) Frenkel defect results neither decrease nor increase in density of substance.
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RELATED QUESTIONS
Explain the following term with suitable examples:
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?
What type of defect is shown by NaCl in
stoichiometric defects, and
non-stoichiometric defects?
Point defect is also known as ____________.
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: 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.
Alkali halids do not show Frenkel defect because ____________.
Silver halides generally show:
Cations are present in the interstitial sites in ______.
Schottky defect is observed in crystals when ______.
Which of the following defects decrease the density?
(i) Interstitial defect
(ii) Vacancy defect
(iii) Frankel defect
(iv) Schottky defect
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.
Given below are two statements:
Statements I: Frenkel defects are vacancy as well as interstitial defects.
Statements II: Frenkel defect leads of colour in ionic solids due to the presence of F-centers.
Choose the most appropriate answer for the statements from the options given below:
The incorrect statement about the imperfections in solids is ______.
Which type of ‘defect’ has the presence of cations in the interstitial sites?
