10 Question-answer on solids and crystals
1. Which of the following is a crystalline solid
(a) Graphite
(b) Calcite
(c) Gallium
(d) Oxygen
Ans: (b)
2. According to Bravis, the number of possible space lattice is
(a) 18
(b) 16
(c) 14
(d) 10
Ans: (c)
3. Which of the following is not the property of a crystalline solid?
(a) Sharp melting point
(b) Flat faces
(c) Isotropic electrical conductivity
(d) Long range order
Ans: (c)
4. The space lattice of diamond is:
(a) Fcc
(b) Bcc with two atoms per unit cell
(c) Bcc with 4 atoms per unit cell
(d) Simple cubic
Ans: ( a)
5. Which one of the following is the weakest kind of bonding in solids
(a) Ionic
(b) Metallic
(c) Vander waals
(d) Covalent
Ans: (c)
6. If there are 4 atoms per unit cell in a solid, the crystal is:
(a) Simple cubic
(b) Body centred cubic
(c) Face-centred cubic
(d) End centred cubic
Ans: ( c)
7. Which of the following has minimum portion of available volume, filled by hard spheres arranged in various structures?
(a) Simple cubic
(b) Face centred cubic
(c) Body centre cubic
(d) Diamond
Ans: (b,d)
8. The coordination number is the number of the
(a) Closest neighboring atoms in a crystal structure
(b) Atoms per unit volume
(c) Atoms per unit cell
(d) Atoms per lattice
Ans: (a)
9. If the physical properties of solids do not depend on the direction, then solid is known as
(a) Anisotropic
(b) Isotropic
(c) Orthotropic
(d) Allotropic
Ans: ( b)
10. If the physical properties of solids depend upon the direction, the property of the crystal is called
(a) Anisotropic
(b) Isotropic
(c) Orthotropic
(d) Allotropic
Ans: ( a)