Point Defects MCQs : Here you will find MCQ Questions related to "Point Defects" in Materials Science. These Point Defects MCQ Questions Will help you to improve your Materials Science knowledge and will prepare you for various Examinations like Competitive Exams, Placements, Interviews and other Entrance Exmaniations
How many types of point defects?
Explanation: There are 3 types of point defects: Stoichiometric defect, Frenkel defect, Schottky defect
Point defects are accounted for when the crystallization process occurs at a very fast rate.
C. Can be yes or no
D. Can not say
Explanation: Point defects are accounted for when the crystallization process occurs at a very fast rate. These defects mainly happen due to deviation in the arrangement of constituting particles. In a crystalline solid, when the ideal arrangement of solids is distorted around a point/ atom it is called a point defect.
Which type of point defect, the ratio of positive and negative ions (Stoichiometric) and electrical neutrality of a solid is not disturbed?
A. Frenkel Defect
B. Schottky defect
C. Stoichiometric Defect
D. All of the above
Explanation: Stoichiometric Defect: In this kind of point defect, the ratio of positive and negative ions (Stoichiometric) and electrical neutrality of a solid is not disturbed. Sometimes it is also known as intrinsic or thermodynamic defects
Which compound mainly shows vacancy and interstitial defects?
C. Both A and B
D. None of the above
Explanation: A non-ionic compound mainly shows vacancy and interstitial defects. An ionic compound shows the same in Frenkel and Schottky defect.
Which defect also known as dislocation defect?
A. Stoichiometric Defect
B. Vacancy defect
C. Interstitial defect
D. Frenkel Defect
Explanation: Frenkel Defect: It is also known as dislocation defect
Which of the following example of Frenkel Defect?
D. Both A and B
Explanation: Frenkel Defect: In ionic solids generally, the smaller ion (cation) moves out of its place and occupies an intermolecular space. In this case, a vacancy defect is created on its original position and the interstitial defect is experienced at its new position. Example: ZnS and AgCl.
Which is not a name given to vacancy in some ionic solid?
C. Color center
D. Luminescence center
Explanation: Other than H-center which is used when a halogen occupies the interstitial position, all the other terms are used for a vacancy in ionic solid. For some ionic solid when there is a vacancy in crystal, an F-center or color enter or luminescence center is formed due to which the ionic solid exhibits different colors.
In which of the following defect the density of the crystal is affected?
A. Schottky defect
B. Frenkel defect
C. Stone-Wales defect
D. Antisite defect
Explanation: The density of the solid crystal in case of the Schottky defect is less than the theoretical density of the material. This happens as the total number of ions in the lattice is less than the theoretical number of ions according to its volume when this defect occurs.
Which type of diffusion occurs due to the exchange of an atom with vacancies?
A. Elimination diffusion
B. Passive diffusion
C. Substitution diffusion
D. Facilated diffusion
Explanation: Substitution as the name suggests it deal with substituting an atom or element in the empty gaps present in crystalline solid which are commonly called as a vacancy.
Which of the following is not the feature of solute and solvent atoms that determine the degree to which former dissolve in latter?
B. Atomic size factor
C. Crystal structure
D. Corrosion factor
Explanation: Corrosion factor determines the rate at which a metal can be corroded it is not related to the solubility of solute and solvent.