CBSE Class 12 Chemistry Solid State Worksheet Set A

Important Questions for NCERT Class 12 Chemistry Solid State

Question. Gold has a face centred cubic lattice with an edge length of the unit cube of 407 pm. Assuming the closest packing, the diameter of the gold atom is
(a) 576.6 pm
(b) 287.8 pm 
(c) 352.5 pm
(d) 704.9 pm

Answer : B

Question. Which is not correct about the Schottky defects?
(a) Both cations and anions are missing from their lattice sites without affecting the stoichiometry of the compound
(b) Because of presence of holes the lattice energy decreases.
(c) The presence of holes causes the density of the crystal to decrease.
(d) The defect increases the electrical conductivity of the solid due to migration of the ions into the holes.

Answer : B

Question. Schottky defect defines imperfection in the lattice structure of 
(a) solid
(b) gas
(c) liquid
(d) plasma

Answer : A

Question. An AB2 type structure is found in
(a) NaCl
(b) CaF²
(c) Al²O³
(d) N²O

Answer : B

Question. An element (atomic mass 100 g/mol) having bcc structure has unit cell edge 400 pm. The density of element is (No. of atoms in bcc, Z = 2). 
(a) 2.144 g/cm³
(b) 7.289 g/cm³
(c) 5.188 g/cm³
(d) 10.376 g/cm³

Answer : C

Question. What is the coordination number of sodium in Na2O? 
(a) 6
(b) 4
(c) 8
(d) 2

Answer : B

Question. The crystal system of a compound with unit cell dimensions "a = 0.387, b = 0.387 and c = 0.504 nm and α = β = 90° and γ = 120°" is : 
(a) cubic
(b) hexagonal
(c) orthorhombic
(d) rhombohedral

Answer : B

Question. If z is the number of atoms in the unit cell that represents the closest packing sequence ..... ABC ABC ......, the number of tetrahedral voids in the unit cell is equal to :
(a) z
(b) 2z
(c) z/2
(d) z/4

Answer : B

Question. The compound, found in nature in gas phase but ionic in solid state is : 
(a) PCl₅
(b) CCl₄
(c) PCl₃
(d) POCl₃

Answer : A

Question. The Ca²⁺ and F– are located in CaF2 crystal, respectively at face centred cubic lattice points and in 
(a) Tetrahedral voids
(b) Half of tetrahedral voids
(c) Octahedral voids
(d) Half of octahedral voids

Answer : A

Question. The coordination number in hcp is 
(a) 6
(b) 12
(c) 18
(d) 24

Answer : B

Question. The space lattice of graphite is 
(a) Cubic
(b) Tetragonal
(c) Rhombic
(d) Hexagonal

Answer : D

Question. Coordination numbers of Zn²⁺ and S^2– in the crystal structure of wurtzite are 
(a) 4, 4
(b) 6, 6
(c) 8, 4
(d) 8, 8

Answer : A

Question. If AgI crystallises in zinc blende structure with I– ions at lattice points. What fraction of tetrahedral voids is occupied by Ag+ ions?
(a) 25%
(b) 50%
(c) 100%
(d) 75%

Answer : B

Question. Which set of following characteristics for ZnS crystal is correct? 
(a) Coordination number (4 : 4); ccp; Zn²⁺ ion in the alternate tetrahedral voids
(b) Coordination number (6 : 6); hcp; Zn²⁺ ion in all tetrahedral voids.
(c) Coordination number (6 : 4); hcp; Zn²⁺ ion in all octahedral voids
(d) Coordination number (4 : 4); ccp; Zn²⁺ ion in all tetrahedral voids.

Answer : A

Question. Molecules/ions and their magnetic properties are given below. 
Molecule/ion Magnetic property
(i) C6H6 (1) Antiferromagnetic
(ii) CrO2 (2) Ferrimagnetic
(iii) MnO (3) Ferromagnetic
(iv) Fe3O4 (4) Paramagnetic
(v) Fe3+ (5) Diamagnetic
The correctly matched pairs in the above is
(a) i-5, ii-3, iii-2, iv-1, v-4
(b) i-3, ii-5, iii-1, iv-4, v-2
(c) i-5, ii-3, iii-1, iv-2, v-4
(d) i-5, ii-3, iii-1, iv-4, v-2

Answer : C

Question. Which one of the following statements about packing in solids is incorrect ?
(a) Coordination number in bcc mode of packing is 8.
(b) Coordination number in hcp mode of packing is 12.
(c) Void space in hcp mode of packing is 32%.
(d) Void space is ccp mode of packing is 26%.

Answer : C

Question. Sodium metal crystallizes in a body centred cubic lattice with a unit cell edge of 4.29Å. The radius of sodium atom is approximately : 
(a) 5.72Å
(b) 0.93Å
(c) 1.86Å
(d) 3.22Å

Answer : C

Question. The existence of a substance in more than one solid modifications is known as 
(a) isomorphism
(b) Polymorphism
(c) Amorphism
(d) Allotropy

Answer : B

Question. An element (atomic mass = 100 g / mol) having bcc structure has unit cell edge 400 pm. Then, density of the element is 
(a) 10.376 g/cm³
(b) 5.188 g/cm³
(c) 7.289 g/cm³
(d) 2.144 g/cm³

Answer : B

Question. A compound is formed by cation C and anion A. The anions form hexagonal close packed (hcp) lattice and the cations occupy 75% of octahedral voids.
The formula of the compound is
(a)C₃A₂
(b)C₃A₄
(c)C₄A₃
(d)C₂A₃

Answer : B

Question. All the metallic elements like iron, copper; non-metallic elements like sulphur, iodine and compounds like NaCl, ZnS form
(a) amorphous solids
(b) crystalline solids
(c) polycrystalline solis
(d) Both (b) and (c)

Answer : B

Question. Some of the physical properties of crystalline solids like refractive index show different values on measuring along different directions in the same crystals. This property is called
(a) isotropy
(b) cleavage property
(c) anisotropy
(d) None of these

Answer : C

Question. Which primitive unit cell has unequal edge lengths (a≠b≠ c) and all axial angles different from 90°?
(a) Hexagonal
(b) Monoclinic
(c) Tetragonal
(d) Triclinic

Answer : D

Question. Identify the type of crystal system of the following
(A) KNO₃ ;  (B) CaCO₃ ;  (C) CaSO₄ ; (D) CuSO₄  5H₂O  
(a) A-Cubic; B-Triclinic; C-Hexagonal; D-Rhombohedral
(b) A-Tetragonal; B-Monoclinic; C-Triclinic; D-Hexagonal
(c) A-Orthorhombic; B-Trigonal; C-Tetragonal; D-Triclinic
(d) A-Rhombohedral; B-Hexagonal; C-Trigonal; D-Orthorhombic

Answer : C

Question. In a face centred cubic lattice, atom A occupies the corner positions and atom B occupies the face centre positions. If one atom of B is missing from one of the face centred points, the formula of the compound is
(a) A₂ B
(b) A B₂
(c) A₂ B₂
(d) A₂ B₅

Answer : D

Question. The lattice points of a crystal of hydrogen iodide are occupied by
(a) HI molecules
(b) H atoms and I atoms
(c) H⁺ cations and I⁻ anions
(d) H₂ molecules and I₂ molecules

Answer : A

Question. The number of octahedral void(s) per atom present at a cubic close packed structure is
(a) 1
(b) 3
(c) 2
(d) 4

Answer : A

Question. In a crystalline solid, having formula XY₂O₄ , oxide ions are arranged in cubic close packed lattice, while cations X are present in tetrahedral voids and cations Y are present in octahedral voids. The percentage of tetrahedral voids occupied by X is
(a) 12.5%
(b) 25%
(c) 50%
(d) 75%

Answer : A

Question. Which type of magnetic behaviour is exhibited by MgFe₂O₄ is ?
(a) Diamagnetic
(b) Paramagnetic
(c) Ferromagnetic
(d) Ferrimagnetic

Answer : D

Question. Element ‘B ’ forms ccp structure and ‘A ’ occupies half of the octahedral voids, while oxygen atoms occupy all the tetrahedral voids. The structure of bimetallic oxide is
(a) A₂BO₄
(b) AB₂O₄
(c)  A₂B₂O
(d) A₄B₂

Answer : B

Question. Which of the following is correct order of packing efficiency?
(a) hcp = fcc > bcc > sc
(b) sc > bcc > hcp = fcc
(c) bcc > sc > hcp < fcc
(d) fcc = hcp > sc > bcc

Answer : A

Question. A metal has bcc structure and the edge length of its unit cell is 3.04 Å. The volume of the unit cell in cm³ will be
(a) 1.6 × 10⁻²¹ cm³
(b) 2.81 × 10⁻²³ cm³
(c) 6.02 × 10⁻²³ cm³
(d) 6.6 × 10⁻²⁴ cm³

Answer : B

Question. An atom forms face centred cubic crystal with density d = 8.92 g / mL and edge length a = 3.6 ×10⁻⁸ cm. The molecular mass of atom in amu is
(a) 98 amu
(b) 63 amu
(c) 32 amu
(d) 93 amu

Answer : B

Question. Sodium metal crystallises in a body centred cubic lattice with a unit cell edge of 4.29 A ° . The radius of sodium atom is approximately
(a) 1.86 Å
(b) 3.22 Å
(c) 5.72 Å
(d) 0.93 Å

Answer : A

Question. Iron exhibits bcc structure at room temperature.
Above 900°C , it transforms to fcc structure. The ratio of density of iron at room temperature to that at 900°C (assuming molar mass and atomic radii of iron remains constant with temperature) is
(a) 3√3/4√2
(b) 4√3/3√2
(c) √3/√2
(d) 1/2

Answer : A

Question. The cubic unit cell of Al (molar mass 27 g mol⁻¹ ) has an edge length of 405 pm. Its density is 2.7 g cm^–3 .
The cubic unit cell is
(a) face centred
(b) body centred
(c) primitive
(d) edge centred

Answer : A

Question. Which of the following compounds is likely to show both Frenkel and Schottky defects in its crystalline form?
(a) AgBr
(b) CsCl
(c) KBr
(d) ZnS

Answer : A

Question. Electrical conductivity of semiconductors increases with increase in
(a) temperature
(b) pressure
(c) volume
(d) None of these

Answer : A

Question. Which of the following is the ratio of packing density of fcc, bcc and simple cubic structures ?
(a) 0.92 : 0.70 : 1
(b) 0.70 : 0.92 : 1
(c) 1 : 0.92 : 0.70
(d) 1 : 0.70 : 0.92

Answer : C

Question. Which of the following has the highest value of energy gap?
(a) Aluminium
(b) Silver
(c) Germanium
(d) Diamond

Answer : D

Question. Which one is not a ferroelectric compound?
(a) KH₂ PO₄
(b) K₄ [Fe(CN)₆ ]  
(c) Rochelle salt
(d) BaTiO₃

Answer : B

Please click the link below to download full pdf file for CBSE Class 12 Chemistry Solid State