Solid State MCQs

Solid State MCQs

A solid has a fixed size and shape that remains constant unless influenced by external conditions. In solids, particles are tightly packed together because of strong intermolecular forces that maintain their fixed positions. This makes solids hard, rigid, and incompressible. When atoms are pushed closer together, the intermolecular forces become repulsive. As thermal energy increases, the kinetic energy of the molecules rises, leading to the transformation of a solid into a liquid.

Na and Mg crystallize in crystals of bcc and fcc form respectively, and 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

How many unit cells are divided equally in a face-centred cubic lattice?

(a) 2
(b) 4
(c) 6
(d) 8

Ferrous oxide has a cubic structure and each unit cell edge is 5.0 Å. Assuming the oxide density is 4.0 g/cm³, the amount of Fe²⁺ and O²⁻ ions in each unit cell will then be:

(a) four Fe²⁺ and four O²⁻
(b) two Fe²⁺ and four O²⁻
(c) four Fe²⁺ and two O²⁻
(d) three Fe²⁺ and three O²⁻

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

For the orthorhombic system, axial ratios are a ≠ b ≠ c and the axial angles are:

(a) α = β = γ ≠ 90°
(b) α ≠ β ≠ γ ≠ 90°
(c) α = β = γ = 90°
(d) α ≠ β ≠ γ = 90°

A crystalline solid:

(a) changes abruptly from solid to liquid when heated.
(b) has no definite melting point.
(c) undergoes deformation of its geometry easily.
(d) has irregular 3-dimensional arrangements.

Copper crystallizes in FCC with a unit cell length of 361 pm. What is the radius of a copper atom?

(a) 128 pm
(b) 157 pm
(c) 181 pm
(d) 108 pm

The total number of voids in 0.5 mol of a compound forming a hexagonal close-packed structure is:

(a) 6.022 × 10²³
(b) 3.011 × 10²³
(c) 9.033 × 10²³
(d) 4.516 × 10²³

Schottky defect in a crystal is observed when:

(a) The ion leaves its normal position and occupies an interstitial location
(b) An unequal number of cations and anions are missing from the lattice
(c) The density of the crystal increases
(d) An equal number of cations and anions are missing from the lattice

Each of the following solids shows the Frenkel defect except:

(a) ZnS
(b) AgBr
(c) AgI
(d) KCl