OBJECTIVE SOLID STATE LEVEL – I
1. If the coordination no. of an element in its crystal lattice is 8, then packing is
(A) fcc (B) hcp
(C) bcc (D) none of the above
2. In a hexagonal closest packing in two layers one above the other, the coordination number of each sphere will be
(A) 4 (B) 6
(C) 8 (D) 9
3. The maximum proportion of available volume that can be filled by hard spheres in diamond is
(A) 0.52 (B) 0.34
(C) 0.32 (D) 0.68
4. The number of molecules in a unit cell of fluorite is
(A) 2 (B) 4
(C) 6 (D) 8
5. 4:4 Co – ordination is found in
(A) ZnS (B) CuCl
(C) AgI (D) Au
6. Which one of the following is a Ferrite?
(A) Na2Fe2O4 (B) MgFe2O4
(C) AlFe4O4 (D) Zn3FeO4
7. When NaCl is doped with MgCl2, the nature of defect produced is
(A) Interstitial defect (B) Schottky defect
(C) Frenkel defect (D) None of these
8. To get n – type doped Semi conductor, impurity to be added to silicon should have the following number of valence electrons
(A) 2 (B) 5
(C) 3 (D) 1
9. Super conductors are derived from compounds of
(A) p – block (B) Lanthanides
(C) Actinides (D) Transition elements
10. At zero Kelvin, most of the ionic crystals possess
(A) Frenkel defect (B) Schottky defect
(C) Metal excess defect (D) No defect
11. Non – stoichiometric metal deficiency is shown in the salts of
(A) All metals (B) Alkali metals
(C) Alkaline earth metals (D) Transition metal
12. Silicon doped with arsenic is
(A) p – type Semiconductor (B) n – type Semiconductor
(C) Like a metallic conductor (D) an insulator
13. A solid has a structure in which W atoms are located at the corners of cubic lattice, O atoms at the centre of edges and Na atom at the centre of the cube. The formula of the compound is
(A) NaWO2 (B) NaWO3
(C) Na2WO3 (D) NaWO4
14. In a face centred cubic arrangement of A and B atoms in which A atoms are at the corners of the unit cell and B atoms at the face centres, one of the A atoms is missing from one corner in unit cell. The simplest formula of compound is
(A) A7B3 (B) AB3
(C) A7B24 (D) A7/8B3
15. A binary solid (A+B-) has a rock salt structure. If the edge length is 400 pm and radius of cation is 75 pm. The radius of anion is
(A) 100 pm (B) 125 pm
(C) 250 pm (D) 325 pm
Level – II
1. A binary solid (A+ B-) has zinc blende structure with B- ions constituting the lattice and
A+ ions occupying 25% tetrahedral holes. The formula of solid is
A+ ions occupying 25% tetrahedral holes. The formula of solid is
(A) AB (B) A2B
(C) AB2 (D) AB4
2. In a metal oxide, the oxide ions are arranged in hexagonal close packing and metal ions occupy two third of the octahedral voids. The formula of the oxide is
(A) Mo (B) M2O3
(C) Mo2 (D) M2O
3. The radius of A+ is 95 pm and that of B- ion is 181 pm. Hence the coordination number of
A+ will be
A+ will be
(A) 4 (B) 6
(C) 8 (D) Un predictable
4. The empty space in hexagonal close packing pattern is
(A) 48% (B) 52.4 %
(C) 26% (D) 70%
5. Which of the following crystallises in bcc structure?
(A) ZnS (B) Na2S
(B) NaCl (D) CsCl
6. The structure of Na2O crystal is
(A) CsCl type (B) NaCl type
(C) ZnS type (D) Anti fluorite
7. A solid AB has NaCl type structure. If the radius of the cation A is 100 pm, then the radius of the anion B will be
(A) 241 pm (B) 414 pm
(C) 225 pm (D) 44.4 pm
8. Doping of silicon with P or Al increasing the conductivity. The difference in the two cases is
(A) P is non – metal whereas Al is a metal
(B) P is a poor conductor while Al is conductor
(C) P gives rise to extra electrons while Al gives rise to holes
(D) P gives rise to holes while Al gives rise to extra electrons
9. In the laboratory, sodium chloride is made by burning sodium in the atmosphere of chlorine. The salt obtained is yellow in colour. The cause of yellow colour is due to
(A) Presence of Na+ ions in the crystal lattice
(B) Presence of Cl- ions in the crystal lattice
(C) Presence of electrons in the crystal lattice
(D) Presence of faced centred cubic crystal lattice
10. The C – C and Si – C interatomic distances are 154 pm and 188 pm. The atomic radius of
Si is
Si is
(A) 77 pm (B) 94 pm
(C) 114 pm (D) 111 pm
11. ZnO is white when cold and yellow when heated, it is due to the development of
(A) Frenkel defect (B) Schottky defect
(C) Metal excess defect (D) Metal deficiency defect
12. The second order Bragg diffraction of X – Rays with ? = 1.0A° from a set of parallel planes in a metal occurs at an angel of 60°. The distance between the Scattering planes in the crystal is
(A) 0.575 A° (B) 1.00 A°
(C) 2.00 A° (D) 1.15 A°
13. A mineral having the formula AB2 crystallizes in the cubic close packed lattice, with the
A atom occupying the lattice points. The Co – ordination number of B atoms and the fraction of the tetrahedral sites occupied by B atoms are
A atom occupying the lattice points. The Co – ordination number of B atoms and the fraction of the tetrahedral sites occupied by B atoms are
(A) 4,100% (B) 6,75%
(C) 1, 25% (D) 6,50%
14. A crystal of lead (II) sulphide has NaCl structure. In this crystal the shortest distance between a Pb+2 ion and S-2 ion is 297 pm. What is the volume of unit cell in lead sulphide?
(A) 209.6×10-24 cm3 (B) 207.8×10-23 cm3
(C) 22.3x10-23 cm3 (D) 209.8×10-23 cm3
15. How many unit cells are present in a cube shaped ideal crystal of NaCl of mass 1.00 g?
(A) 5.14×1021 (B) 1.28×1021
(C) 1.71×1021 (D) 2.57×1021
No comments:
Post a Comment