Advertisements
Advertisements
प्रश्न
Why is FeO (s) not formed in stoichiometric composition?
Advertisements
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.
APPEARS IN
संबंधित प्रश्न
non-stoichiometric defects?
Out of NaCl and AgCl, which one shows Frenkel defect and why?
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 ____________.
Schottky defect defines imperfection in the lattice structure of ____________.
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.
Alkali halids do not show Frenkel defect because ____________.
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.
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.
If NaCl is doped with 10–4 mole percent of SrCl2 the concentration of cation vacancies will be
Schottky defect is noticed in ______
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:
Which type of ‘defect’ has the presence of cations in the interstitial sites?
