AB 2 type structure is found in a. Nacl b. Al2 O 3 c. CaF 2 d. N 2 O Ans. c (5)
a. Z b. 2 Z c. Z/2 d. Z/4 Ans. b Explanation : Number of tetrahedral voids in the unit cell = 2 x number of atoms = 2 Z (9)
a. Octahedral close packing b. Hexagonal close packing c. Tetragonal close packing d. Cubic close packing Ans. d Explanation : It represents ccp arrangement (9)
a. 26 % b. 48 % c. 23 % d. 32 % Ans. d Explanation : Packing efficiency in bcc lattice = 68 % vacant space in bcc lattice = 100- 68 = 32 % (7)
Cs + is a. Equal to that of Cl – , that is 6 b. Equal to that of Cl – , that is 8 c. Not Equal to that of Cl – , that is 6 d. Not Equal to that of Cl – …
a. Cl– ions are in fccarrangement b. Na+ ions has coordination number 4 c. Cl– ions has coordination numnber 6 d. Each unit cell contains 4NaCl molecules Ans. b (17)
a. 2 b. 3 c. 4 d. 6 Ans. c (16)
a. Cl – ions form fcc lattice and Na+ ions occupy all octahedral voids of the unit cell b. Ca 2+ ions form fcc lattice and F – ions occupy all the eight tetrahedral voids of the unit cell c. O 2- ions …
Rb+ and I– are 1.46 Å and 2.16 Å . The most probable type of structure exhibited by it is a. CsCl type b. Zns type c. NaCl type d. CaF type Ans. c (26)
a. All octahedral holes b. All tetrahedral holes c. Half number of octahedral holes d. Half number of tetrahedral holes Ans. d Explanation : In zinc blende half number of tetrahedral holes are filled bu zinc atoms. (30)
A+and B– ions are 0.98 x 10-10 m and 1.81 x 10 m-10 . The coordination number of each ion in AB is a. 6 b. 4 c.8 d. 2 Ans. a (35)
a. 454 b. 804 c. 852 d. 908 Ans. d (8)
63. 55g mol -1 ) has an edge length of 362 pm. Its denstiy is 8.92g cm -3 . The type of unit cell is a. Primitive b. Face centered c. Body centered d. end centered Ans. b (19)
2.72 g cm -3 . The molar mass of the metal is a. 20 g mol -1 b. 40g mol -1 c. 30 g mol -1 d. 28 g mol -1 Ans. d (7)
a. 100 b. 250 c. 125 d. 150 e. 50 Ans. d (9)
a. 10.376 g/cm3 b. 5.188 g/ cm3 c. 7.289 g/cm3 d. 2.144 g/cm3 Ans. b (9)
a. 154 pm b. 352 pm c. 527 pm d. 264 pm Ans. b (18)
50 Å . Assuming density of the oxide as 4.0g – cm -3 then the number of Fe2+ and O2- ions present in each unit cell will be a. Four Fe2+ and four O2- b. Two Fe2+ and four O2- …
λ = 1 Å from a set of parallel planes in a metal occurs at an angle of 60º . The distance between the scattering planes in the crystal is a. 0.575 Å b. 1.00 Å c. 2.00Å d. 1.15 …
a. 48 % and 26 % b. 30 % and 26 % c. 26 % and 32 % d.32% and 48 % Ans. c (11)
5 Å which crystallize in cubic lattice. If the density is 2g/ cc then find the radius of metal atoms. (N A = 6 x 10 23 ) Give the answer in pm a. 217 pm b. 210 pm c. 220 …
a. 2.57 x 10 21 unit cells b. 5. 14 x 1021 unit cells c. 1.28 x 10 21 unit cells d. 1. 71 x 1021 unit cells Ans. a (5)
4.2 Å 8.6 Å and 8.3 Å given the molecular mass of the solute is 155 g mol -1 and that of density is 3.3 g/ cc, the number of formula units per unit cell is a. 2 b. 3 c. …
2.165 x 103 kg m -3 while its X – rays density is 2.178 x 103 kg m -3 . The fraction of unoccupied sites in sodium chloride crystal is a. 5. 96 x 10-3 b. 5.96 c. 5.96 x 10-2 d. …
2.64Å. What is the difference in energy between K- shell an L – shell in Mo assuming a first-order diffraction (sin 7.75° = 0.1349) a. 36.88 x 10-19 j b. 27.88 x 10 10-16 j c. 63. 88 x 10 10-17 …
a. 15° b. 45° c. 30° d. 60° Ans. c (16)
a. 1.0 pm b. 2. 0 nm c. 0.1 nm d. 2.0 pm Ans. d (24)
a. √2a b. a c. 3/2 (a) d. a/2 Ans. d Explanation : Nearest distance between tetrahedral voids in a fcc lattice is a/2 (43)
Csl 3 , is a. It is covalent molecule b. it contains Cs3+ and I –3 c. It contains Cs+ and I –3 ions d. It contains Cs+ , I – and lattice I – molecule Ans. b (13)
a. It is covalent compound b. it contains Cs3+ and Br – ions c. It contains Cs+ and Br3– ions d. It contains Cs+ , Br– and lattice Br 2 molecule Ans. c (6)
r Na + / r Cl – = 0.55 and r k+ / r Cl– = 0. 74. Calculate the ratio of the side of the unit cell for KCl to that of NaCl a. 1.123 b. 0.891 c. 1.414 …
a. 1/2 , 1/ 8 b. 1 , 1/4 c. 1/2 , 1/ 2 d. 1/4 , 1/ 8 Ans. a (8)
a. 74 b. 26 c. 20 d. 16 Ans. b Explanation : ABAB… is hexagonal close packing in which space occupied = 74 % and empty space = 26 (5)
a. ABO 2 b. A 2BO2 c. A2 B3 O4 d. AB 2 O 2 Ans. d (15)
I– ions at lattice points. What fraction of tetrahedral voids is occupied by Ag + ions a. 25 % b. 50 % c. 100 % d. 75 % Ans. b (4)
a. X2 Y3 b. X2 Y c. X 3 Y 4 d. X 4 Y 3 Ans. d (7)
a. Na b. Mg c. Al d. None of these Ans. b Explanation : Coordination number in hcp = 12 Coordination number in Mg is also = 12 (7)