Last seen: Jan 13, 2022
(a, d) Explanation: When KCl is heated in vapour of K, some of the Cl leave their lattice site and create anion vacancies. This chloride ion wants...
(b, c) Explanation: Silicon (valence electron – 4) doped with electron rich impurity is an n-type semiconductor due to extra electron and the delo...
(a, b) Explanation: In p-type semiconductor, the conductivity is due to existence of hole. When electric field is applied to p-type semiconductor ...
(a, b, d) Explanation: In metal, valence band overlap with conduction band. The gap between valence band and conduction band is negligible and val...
(c, d) Explanation: Statements (c) and (d) can be correctly written as (c) Impurity defect changes the density of substance as impurity has differ...
(d) 8 tetrahedral voids within the unit cells. Explanation: In the cubic close packing the unit cell has 8 tetrahedral voids within it and are loc...
(a) Frenkel defect Explanation: In Frenkel defect, some cations occupy interstitial site and hence it is also called dislocation defect.
(b) fee > bee simple cubic Explanation: Packing efficiency in different types of unit cells can be tabulated as Unit cell Pack...
(a) all the domains get oriented in the direction of magnetic field Explanation: Ferromagnetic solids can be permanently magnetised and then all t...
(d) The fraction of octahedral or tetrahedral voids occupied depends upon the radii of the ions occupying the voids. Explanation: The fraction of ...
(b) Ferromagnetic substances cannot be magnetized permanently Explanation: Ferromagnetic species are strongly attracted in the magnetic field and ...
(b) n-type semiconductor Explanation: Silicon has four valence electrons. If it is doped with an electron rich impurity, the extra electron become...
(d) Electronic defect Explanation: When electron rich or electron deficient impurity is added to a perfect crystal, it introduces electronic defec...
(c) 4 Explanation: Coordination number in a square closed packed structure in two dimensions is equal to 4.
(a) Cl– ions form fee lattice and Na+ ions occupy all octahedral voids of the unit cell. Explanation: NaCl crystals have rock salt structure havin...
(d) In this arrangement, spheres of the fourth layer are exactly aligned with those of the first layer. Explanation: Hexagonal close packing can b...
(c) 32 Explanation: Packing efficiency for bcc arrangement is 68% which represents total filled space in the unit cell. Hence, empty space in a bo...
(b) hep and ccp Explanation: Packing efficiency: It is the percentage of total filled space by particles Packing efficiency = Volume occupied by...
(a) A and B Explanation: AgBr shows both Schottky and Frenkel defects. In AgBr, both Ag+ and Br ions are absent from the lattice causing Schottky ...
(b) 8 Explanation: Fee unit cell contains 8 tetrahedral voids at centre of each 8 smaller cube of a unit cell.