CBSE Class 12 Chemistry The Solid State MCQs Set B

Question: Which of the following is an amorphous solid ?
(a) Graphite (C)
(b) Quartz glass (SiO₂ )
(c) Chrome alum
(d) Silicon carbide (SiC)

Answer : B

Question: Which of the following elements is a semiconductor ?
(a) Na
(b) Al
(c) Fe
(d) Ge

Answer : D

Question: NaCl typecrystal (with coordination no. 6 : 6) can be converted into CsCl type crystal (with coordination no. 8 : 8) by applying
(a) high temperature
(b) high pressure
(c) high temperature and high pressure
(d) low temperature and low pressure

Answer : B

Question: Which of the following solids is not an electrical conductor?
(a) Mg (s)
(b) TiO (s)
(c) I₂ (s)
(d) H₂O (s)

Answer : C

Question: In Zinc blende structure
(a) zinc ions occupy half of the tetrahedral sites
(b) each Zn^2- ion is surrounded by six sulphide ions
(c) each S^2- ion is surrounded by six Zn²⁺ ions
(d) it has fee structure

Answer : C

Question: 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 an irregular 3-dimensional arrangements

Answer : A

Question: The coordination number of Y will be in the XY types of crystal:
(a) 6
(b) 8
(c) 12
(d) 4

Answer : A

Question: Which type of semiconductor is obtained by doping Si with Bi ?
(a) n-type
(b) p-type
(c) pnp-type
(d) npn-type

Answer : A

Question: Crystals can be classified into basic crystal units, equal to
(a) 7
(b) 4
(c) 14
(d) 2

Answer : A

Question: The edge length of fee cell is 508 pm. If radius of cation is 110 pm, the radius of anion is
(a) 110 pm
(b) 220 pm
(c) 285 pm
(d) 144 pm

Answer : D

Question: Graphite cannot be classified as ______.
(a) conducting solid
(b) network solid
(c) covalent solid
(d) ionic solid

Answer : D

Question: How many lithium atoms are present in a unit cell with edge length 3.5 Å and density 0.53 g cm-3? (Atomic mass of Li = 6.94):
(a) 2
(b) 1
(c) 4
(d) 6

Answer : A

Question: Which of the following is an example of a covalent solid ?
(a) Silicon
(b) Sulphur
(c) Phosphorus
(d) Iodine

Answer : A

Question: In Simple cubic lattice, a unit cell contains how many atoms
(a) 2
(b) 4
(c) 1
(d) 8

Answer : C

Question: 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

Answer : B

Question: How many three dimensional crystal lattice are possible?
(a) 20
(b) 7
(c) 14
(d) 10

Answer : C

Question: Which of the following crystals does not exhibit Frenkel defect?
(a) AgBr
(b) AgCl
(c) KBr
(d) ZnS

Answer : C

Question: Most crystals show good cleavage because their atoms, ions or molecules are
(a) weakly bonded together
(b) strongly bonded together
(c) spherically symmetrical
(d) arranged in planes

Answer : D

Question: 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

Answer : B

Question: In which of the following crystals alternate tetrahedral voids are occupied?
(a) NaCl
(b) ZnS
(c) CaF₂
(d) Na₂O

Answer : B

Question: With which element, the conductivity of ReO₃ is matching ?
(a) Copper
(b) Zinc
(c) Iron
(d) Aluminium

Answer : A

Question: Silver halides generally show
(a) Schottky defect
(b) Frenkel defect
(c) Both Frenkel and Schottky defects
(d) cation excess defect

Answer : C

Question: Graphite is a good conductor of electricity due to the presence of ______.
(a) lone pair of electrons
(b) free valence electrons
(c) cations
(d) anions\

Answer : B

Question: 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

Answer : B

Question: The arrangement ABC ABC .......... is referred to as
(a) Octahedral close packing
(b) Hexagonal close packing
(c) Tetrahedral close packing
(d) Cubic close packing

Answer : D

Question: 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

Answer : C

Question: The major binding force of diamond, silicon and quartz is
(a) electrostatic force
(b) electrical attraction
(c) covalent bond force
(d) non-covalent bond force

Answer : C

Question: Select highest electrical conductor and thermal conductor from the following.
(a) Si
(b) Li
(c) NaCl
(d) Ice

Answer : B

Question: 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

Answer : C

Question: The number of octahedral voids present in a lattice is A. The number of closed packed particles, the number of tetrahedral voids generated is B the number of closed packed particles
(a) A- equal, B- half
(b) A- twice, B- equal
(c) A- twice , B- half
(d) A- equal, B- twice

Answer : D

Question: p-type semiconductors are formed When Si or Ge are doped with
(a) group 14 elements
(b) group 15 elements
(c) group 13 elements
(d)group 18 elements

Answer : C

Question: Which of the following statements about amorphous solids is incorrect ?
(a) They melt over a range of temperature
(b) They are anisotropic
(c) There is no orderly arrangement of particles
(d) They are rigid and incompressible

Answer : B

Question: Which theory is useful in explaining electrical conductivity in conductors and semiconductors ?
(a) Pauli's principle
(b) Avogadro's theory
(c) band theory
(d) Hybridisation theory

Answer : C

Question: The number of atoms per unit cell of bcc structure is
(a) 1
(b) 2
(c) 4
(d) 6

Answer : B

Question: Solid CH₄ is
(a) ionic solid
(b) covalent solid
(c) molecular solid
(d) does not exist

Answer : C

Question: Which of the following is a network solid ?
(a) SO₂ (solid)
(b) I2
(c) Diamond
(d) H2O (Ice)

Answer : C

Question: _____ of the following is a crystalline solid.
(a) Glass
(b) Rubber
(c) Plastic
(d) Sugar

Answer : D

Question: Which one of the following is non-crystalline or amorphous?
(a) Diamond
(b) Graphite
(c) Glass
(d) Common Salt

Answer : C

Question: Iodine molecules are held in the crystals lattice by ______.
(a) london forces
(b) dipole-dipole interactions
(c) covalent bonds
(d) coulombic forces

Answer : A

Question: What is the number of atoms in face centred cube ?
(a) 2
(b) 1
(c) 4
(d) 6

Answer : C

Question: Which of the following is not the characteristic of ionic solids?
(a) Very low value of electrical conductivity in the molten state.
(b) Brittle nature.
(c) Very strong forces of interactions.
(d) Anisotropic nature.

Answer : A