1.Which one of the following is non-crystalline or amorphous?
(a) Diamond
(b) Graphite
(c) Glass
(d) Common Salt
2. Alkali halids do not show Frenkel defect because
(a) cations and anions have almost equal size
(b) there is a large difference in size of cations and anions
(c) cations and anions have low coordination number
(d) anions cannot be accommodated in voids
3.Frenkel defect is also known as ________.
(i) stoichiometric defect
(ii) dislocation defect
(iii) impurity defect
(iv) non-stoichometric defect
4.The density of a metal which crystallises in bcc lattice with unit cell edge length 300 pm and
molar mass 50 g mol-1 will be
(a) 10 g cm-3
(b) 14.2 g cm-3
(c) 6.15 g cm-3
(d) 9.3 2 g cm-3
5.An element with atomic mass 100 has a bcc structure and edge length 400 pm. The density of
element is
(a) 10.37 g cm-3
(b) 5.19 g cm-3
(c) 7.29 g cm-3
(d) 2.14 g cm-3
6.Which of the following crystals does not exhibit Frenkel defect?
(a) AgBr
(b) AgCl
(c) KBr
(d) ZnS
7.What type of stoichiometric defect is shown by ZnS?
(a) Schottky defect
(b) Frenkel defect
(c) Both Frenkel and Schottky defects
(d) Non-stoichiometric defect
8.Silver halides generally show
(a) Schottky defect
(b) Frenkel defect
(c) Both Frenkel and Schottky defects
(d) cation excess defect
9.Which of the following will have metal deficiency defect?
(a) NaCl
(b) FeO
(c) KCl
(d) ZnO
10.In which pair most efficient packing is present?
(a) hep and bcc
(b) hep and ccp
(c) bcc and ccp
(d) bcc and simple cubic cell
11.What is the effect of Frenkel defect on the density of ionic solids?
(a) The density of the crystal increases
(b) The density of the crystal decreases
(c) The density of the crystal remains unchanged
(d) There is no relationship between density of a crystal and defect present in it
12.In a Schottky defect
(a) an ion moves to interstitial position between the lattice points
(b) electrons are trapped in a lattice site
(c) some lattice sites are vacant
(d) some extra cations are present in interstitial space
13.Edge length of unit cell of chromium metal is 287 pm with bcc arrangement. The atomic
radius is of the order
(a) 287 pm
(b) 574 pm
(c) 124.27 pm
(d) 143.5 pm
14. Close packing is maximum in the crystal which is
(a) bcc
(b) fcc
(c) simple cubic
(d) end centred cubic
15. In a solid lattice, the cation has left a lattice site and is located at an interstitial position. The
lattice defect is
(a) n-type
(b) p-type
(c) Frenkel defect
(d) Schottky defect
16.In a body centred unit cell, the number of atoms present is
(a) 1
(b) 2
(c) 3
(d) 4
17. In a trigonal crystal
(a) a = b = c, α = ß = γ ≠ 90°
(b) a = b ≠ c, α = ß = γ = 90°
(c) a ≠ b ≠ c, α = ß = γ = 90°
(d) a = b ≠ c, α = ß = 90°, γ = 120°
18.The appearance of colour in solid alkali metal halides is generally due to
(a) Schottky defect
(b) Frenkel defect
(c) F-centre
(d) Interstitial position
19.The empty space within hep arrangement is
(a) 34%
(b) 47.6%
(c) 32%
(d) 26%
20.A crystal system with axes a ≠ b ≠ c and angles α ≠ ß ≠ γ ≠ 90° corresponds to
(a) monoclinic
(b) triclinic
(c) cubic
(d) tetragonal
21.How many space lattices are possible in a crystal?
(i) 23
(ii) 7
(iii) 230
(iv) 14
22.In a simple cubic, body-centred cubic and face-centred cubic structure, the ratio of the
number of atoms present is respectively
a)8:1:6
b)1:2:4
c)4:2:1
d)4:2:3
23. Na and Mg crystallize in crystals of bcc and fcc form respectively and then the amount of Na
and Mg atoms present in their respective crystal unit cells is:
a)4 and 2
b)9 and 14
c)14 and 9
d)2 and 4.
24.Which of the following is true about the value of refractive index of quartz glass?
(i) Same in all directions
(ii) Different in different directions
(iii) Cannot be measured
(iv) Always zero
25. Iodine molecules are held in the crystals lattice by ____________.
(i) london forces
(ii) dipole-dipole interactions
(iii) covalent bonds
(iv) coulombic forces
