NEET Chemistry The Solid State MCQs Set B

Question: In a unit cell, atoms A, B, C and D are present at corners, face-centres, body-centre and edge-centre respectively in a cubic unit cell. The total number of atoms present per unit cell is

• a) 4
• b) 8
• c) 15
• d) 27

Answer: 8

Question: In a unit cell, atoms A, B, C and D are present at half of total corners, all face-centres, body-centre and one third of all edge-centres respectively. Then formula of unit cell is

• a) AB₃CD₃ 
• b) ABCD
• c) AB₆C₂D₄
• d) AB₆C₂D₂

Answer:  AB₆C₂D₂

Question: In a unit cell, atoms A, B, C and D are present at corners, face-centres, body-centre and edge-centres respectively. If atoms touching one of the plane passing through two diagonally opposite edges are removed,then formula of compound is

• a) ABCD₂
• b) ABD₂
• c) AB₂D₂ 
• d) AB₄D₅

Answer:  AB₄D₅

Question: In a CsCl structure, if edge length is x, then distance between one Cs atom and one Cl atom is

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: The correct statement about, CCP structure is

• a) Packing fraction = 26%
• b) Coordination number = 6
• c) Unit cell is face centred cubic
• d) AB–AB type of packing

Answer: Unit cell is face centred cubic

Question: In a NaCl structure, if positions of Na atoms and Cl atoms are interchanged, then in the new unit cell

• a) Na atom is present at body centre
• b) Cl atom is present at face centre
• c) Na atom is present in tetrahedral voids
• d) Cl atom is present in octahedral voids

Answer: Cl atom is present in octahedral voids

Question: If radius of a metal atom (A) is 5 pm and radius of an electronegative atom (B) is 20 pm, then in the unit cell

• a) A in octahedral voids, B in FCC unit
• b) A in FCC unit, B in tetrahedral void
• c) A in BCC unit, B in cubic void
• d) A in tetrahedral void, B in FCC unit

Answer: A in tetrahedral void, B in FCC unit

Question: Then ratio of densities of FCC and BCC unit cells is

• a) 1/4
• b) 4
• c) 1/16
• d) 16

Answer: 1/4

Question:  In a unit cell containing X²⁺, Y³⁺ and Z^2– where X²⁺ occupies 1/8th of tetrahedral voids, Y³⁺ occupies 1/2 of octahedral voids and Z^2– forms ccp structure. Then formula of compound is

• a) X₂Y₄Z
• b) XY₂Z₄
• c) XY₃Z₄ 
• d) X₄YZ₂

Answer:  XY₂Z₄

Question: On rising temperature and decreasing pressure in CsCl solid

• a) C.N. of metal ion increases from 6 to 8
• b) Number of formula unit per unit cell (Z) changes from one to four
• c) Density of unit cell is increased
• d)

  

Answer: Number of formula unit per unit cell (Z) changes from one to four

Question: In a ccp type structure, if half of the face-centred atoms are removed, then percentage void in unit cell is approximately

• a) 54%
• b) 46.25%
• c) 63%
• d) 37%

Answer: 54%

Question: In a BCC unit cell, if half of the atoms per unit cell are removed, then percentage void is

• a) 68%
• b) 32%
• c) 34%
• d) 66%

Answer: 66%

Question: Number of atoms per unit cell, if atoms are present at the corner of unit cell and 2 atoms at each body diagonal

• a) 9
• b) 10
• c) 6
• d) 4

Answer: 9

Question: Some of the molecular solids upon heating produces small amount of electricity, hence solid is

• a) Piezoelectric
• b) Pyroelectric
• c) Ferrielectric
• d) Ferroelectric

Answer: Pyroelectric

Question: NaCl becomes paramagnetic at high temperature due to

• a) Formation of F-centre
• b) Molten state
• c) Change in oxidation state
• d) Conversion of Na⁺ to Na

Answer: Formation of F-centre

Question: Number of unit cells in 10 g NaCl

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: Second nearest neighbour in CsCl solid

• a) 8
• b) 6
• c) 16
• d) 10

Answer: 6

More Questions...........................................

Question: The ratio of number of rectangular plane and diagonal plane in a cubic unit cell

• a) 1 : 2
• b) 3 : 1
• c) 2 : 3
• d) 3 : 4

Answer: 1 : 2

Question: In a calcium fluoride structure, the co-ordination number of cation and anion is respectively.

• a) 6, 6
• b) 8, 4
• c) 4, 4
• d) 4, 8

Answer: 8, 4

Question: In which of the following defect density increases?

• a) Schottky defect
• b) Frenkel defect
• c) F-centre
• d) Impurity defect

Answer: Impurity defect

Question: Glass is a

• a) Micro-crystalline solid
• b) Super cooled liquid
• c) Gel
• d) Polymeric mixture

Answer: Super cooled liquid

Question: The vacant space in bcc lattice unit cell is

• a) 23%
• b) 32%
• c) 26%
• d) 48%

Answer: 32%

Question: The correct statement regarding defects in crystalline solids is

• a) Frenkel defect is a dislocation defect
• b) Frenkel defect is found in halides of alkaline metals
• c) Schottky defects have no effect on the density of crystalline solids
• d) Frenkel defects decrease the density of crystalline solids

Answer: Frenkel defect is a dislocation defect

Question: If a is the length of the side of a cube, the distance between the body centered atom and one corner atom in the cube will be

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: A given metal crystallizes out with a cubic structure having edge length of 361 pm. If there are four metal atoms in one unit cell, what is the radius of one atom?

• a) 108 pm
• b) 40 pm
• c) 127 pm
• d) 80 pm

Answer: 127 pm

Question: The number of carbon atoms per unit cell of diamond unit cell is

• a) 8
• b) 6
• c) 1
• d) 4

Answer: 8

Question: A metal crystallizes with a face-centered cubic lattice. The edge of the unit cell is 408 pm. The diameter of the metal atom is

• a) 144 pm
• b) 204 pm
• c) 288 pm
• d) 408 pm

Answer: 288 pm

Question: The number of octahedral void(s) per atom present in a cubic close-packed structure is

• a) 2
• b) 4
• c) 1
• d) 3

Answer: 1

Question: Structure of a mixed oxide is cubic close packed (ccp). The cubic unit cell of mixed oxide is composed of oxide ions. One fourth of the tetrahedral voids are occupied by divalent metal A and the octahedral voids are occupied by a monovalent metal B. The formula of the oxide is

• a) ABO₂ 
• b) A₂BO₂ 
• c) A₂B₃O₄ 
• d) AB₂O₂

Answer:  AB₂O₂

Question:  A metal has a fcc lattice. The edge length of the unit cell is 404 pm. The density of the metal is 2.72 g cm^–3.The molar mass of the metal is (N_A Avogadro's constant=6.02×10²³ mol^–1) 

• a) 30 g mol^–1
• b) 27 g mol^–1
• c) 20 g mol^–1
• d) 40 g mol^–1

Answer:  27 g mol^–1

Question: Among the following which one has the highest cation to anion size ratio?

• a) CsI
• b) CsF
• c) LiF
• d) NaF

Answer: CsF

Question: AB crystallizes in a body centred cubic lattice with edge length 'a' equal to 387 pm. The distance between two oppositively charged ions in the lattice is

• a) 335 pm
• b) 250 pm
• c) 200 pm
• d) 300 pm

Answer: 335 pm

Question:  A solid compound XY has NaCl structure. If the radius of the cation is 100 pm, the radius of the anion (Y^–) will be

• a) 241.5 pm
• b) 165.7 pm
• c) 275.1 pm
• d) 322.5 pm

Answer: 241.5 pm

Question: Lithium metal crystallises in a body centred cubic crystal. If the length of the side of the unit cell of lithium is 351 pm, the atomic radius of the lithium will nearly be

• a) 152 pm
• b) 75 pm
• c) 300 pm
• d) 240 pm

Answer: 152 pm

Question: Copper crystallises in a face-centred cubic lattice with a unit cell length of 361 pm. What is the radius of copper atom in pm ?

• a) 157
• b) 181
• c) 108
• d) 128

Answer: 128

Question: If 'a' stands for the edge length of the cubic systems : simple cubic, body centred cubic and face centred cubic, then the ratio of radii of the spheres in these systems will be respectively

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: Percentage of free space in a body centred cubic unit cell is

• a) 28%
• b) 30%
• c) 32%
• d) 34%

Answer: 32%

Question: With which one of the following elements silicon should be doped so as to give p-type of semiconductor ?

• a) Boron
• b) Germanium
• c) Arsenic
• d) Selenium

Answer: Boron

Question: Which of the following statements is not correct ?

• a) The number of Bravais lattices in which a crystal can be categorized is 14
• b) The fraction of the total volume occupied by the atoms in a primitive cell is 0.52
• c) Molecular solids are generally volatile
• d) The number of carbon atoms in a unit cell of diamond is 4

Answer: The number of carbon atoms in a unit cell of diamond is 4

Question: The fraction of total volume occupied by the atoms present in a simple cube is

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question:   If NaCl is doped with 10^–4 mol % SrCl₂ , the concentration of cation vacancies will be (N_A= 6.02×10²³ mol^–1)

• a) 6.02×10¹⁴ mol^–1
• b) 6.02×10¹⁵ mol^–1 
• c) 6.02×10¹⁶ mol^–1
• d) 6.02×10¹⁷ mol^–1

Answer:  6.02×10¹⁷ mol^–1

Question: The appearance of colour in solid alkali metal halides is generally due to

• a) F-centres
• b) Schottky defect
• c) Frenkel defect
• d) Interstitial positions

Answer: F-centres

Question:  CsBr crystallises in a body centred cubic lattice. The unit cell length is 436.6 pm. Given that the atomic mass of Cs = 133 and that of Br = 80 amu and Avagadro number being 6.02 × 10²³ mol^–1, the density of CsBr is

• a) 42.5 g/cm³
• b) 0.425 g/cm³
• c) 8.25 g/cm³
• d) 4.25 g/cm³

Answer:  4.25 g/cm³

Question: In a face-centered cubic lattice, a unit cell is shared equally by how many unit cells?

• a) 8
• b) 4
• c) 2
• d) 6

Answer: 6

Question: Ionic solids, with Schottky defects, contain in their structure

• a) Cation vacancies only
• b) Cation vacancies and interstitial cations
• c) Equal number of cation and anion vacancies
• d) Anion vacancies and interstitial anions

Answer: Equal number of cation and anion vacancies

Question:  The number of atoms in 100 g of an FCC crystal with density d = 10 g/cm³ and cell edge equal to 100 pm, is equal to

• a) 2 × 10²⁵
• b) 1 × 10²⁵
• c) 4 × 10²⁵
• d) 3 × 10²⁵

Answer:  4 × 10²⁵

Question: If we mix a pentavalent impurity in a crystal lattice of germanium, what type of semiconductor formation will occur?

• a) n-type semiconductor
• b) p-type semiconductor
• c) Both (1) & (2)
• d) None of these

Answer: n-type semiconductor

Question: The intermetallic compound LiAg crystallizes in cubic lattice in which both lithium and silver have coordination number of eight. The crystal class is

• a) Face-centred cube
• b) Simple cube
• c) Body-centred cube
• d) None of these

Answer: Simple cube

Question: Schottky defect in crystals is observed when

• a) Density of the crystal is increased
• b) Unequal number of cations and anions are missing from the lattice
• c) An ion leaves its normal site and occupies an interstitial site
• d) Equal number of cations and anions are missing from the lattice

Answer: Equal number of cations and anions are missing from the lattice

Question: An element (atomic mass = 100 gm/mol) having BCC structure has unit cell edge 400 pm. The density of element is

• a) 7.289 gm/cm³
• b) 2.144 gm/cm³
• c) 10.376 gm/cm³ 
• d) 5.188 gm/cm³

Answer:  5.188 gm/cm³

Question: The edge length of rock salt type unit cell is 508 pm. If the radius of the cation is 110 pm, the radius of the anion assuming NaCl type structure is

• a) 144 pm
• b) 398 pm
• c) 288 pm
• d) 618 pm

Answer: 144 pm

Question:  The second order Bragg diffraction of X-rays with λ = 1.00 Å from a set of parallel planes in a metal occurs at an angle 60°. The distance between the scattering planes in the crystal is

• a) 2.00 Å
• b) 1.00 Å
• c) 0.575 Å
• d) 1.15 Å

Answer:  1.15 Å

Question: In crystals of which one of the following ionic compounds would you expect maximum distance between centres of cations and anions?

• a) CsI
• b) CsF
• c) LiF
• d) LiI

Answer: CsI

Question: In cube of any crystal A-atom placed at every corners and B-atom placed at every centre of face. The formula of compound

• a) AB
• b) AB₃
• c) A₂B₂
• d) A₂B₃

Answer:  AB₃

Question:  The pyknometric density of sodium chloride crystal is 2.165 × 10³ kg m^–3 while its X-ray density is 2.178 × 10³ kgm^–3. The fraction of unoccupied sites in sodium chloride crystal is

• a) 5.96
• b) 5.96 × 10^–2
• c) 5.96 × 10^–1 
• d) 5.96 × 10^–3

Answer:  5.96 × 10^–3

Question: Coordination number in ABAB... type arrangement is

• a) 6
• b) 8
• c) 12
• d) 4

Answer: 12

Question: A compound formed by elements X and Y crystallizes in a cubic structure in which the X atoms are at the corners of a cube and the Y atoms are at the face-centres. The formula of the compound is

• a) XY₃
• b) X₃Y 
• c) XY
• d) XY₂

Answer:  XY₃

Question: A given metal crystallizes out with a cubic structure having edge length of 361 pm. If there are four metal atoms in one unit cell, what is the radius of one atom?

• a) 108 pm
• b) 40 pm
• c) 127 pm
• d) 80 pm

Answer: 127 pm

Question: In which of the following defect density increases?

• a) Schottky defect
• b) Frenkel defect
• c) F-centre
• d) Impurity defect

Answer: Impurity defect

Question: In a calcium fluoride structure, the co-ordination number of cation and anion is respectively.

• a) 6, 6
• b) 8, 4
• c) 4, 4
• d) 4, 8

Answer: 8, 4