A Complete Resource Book in Chemistry for JEE Main

Atul Singhal

Chapter 2

Solid State - all with Video Answers

Educators

Chapter Questions

Problem 1

Which of the following is not a feature of solids?
(a) definite mass and volume
(b) frequent fluidity
(c) rigidity
(d) definite shape

Supratim Pal

Supratim Pal

Numerade Educator

Problem 2

Which of the following is not a characteristic of amorphous solids?
(a) have sharp melting point
(b) have non-orderly or very short-range orderly arrangement
(c) show isotropy
(d) have tendency to undergo irregular cleavage

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Problem 3

Which of the following is not a property of crystalline solids?
(a) show isotropy
(b) have a sharp melting point
(c) have anisotropic nature
(d) have a long-range orderly arrangement

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Problem 4

Which of the following is a non-crystalline solids' pair?
(a) diamond, wood
(b) glass, table salt
(c) wood, glass
(d) sucrose, glass

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Problem 5

Which of the following is a molecular solid?
(a) $\mathrm{I}_{2}$
(b) wax
(c) ice
(d) all of these

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Problem 6

Which type of solids here are generally good conductors of electricity?
(a) metallic
(b) covalent
(c) ionic
(d) molecular

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Problem 7

Among the following which is/are not crystalline solid(s)?
(a) glass
(b) sodium chloride
(c) sucrose
(d) both (b) and (c)

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Problem 8

Which of the following has hexagonal structure?
(a) diamond
(b) sodium chloride
(c) graphite
(d) both (a) and (c)

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Problem 9

The total number of crystal systems and the number of Bravais lattices are respectively
(a) 7,7
(b) 7,14
(c) 14,14
(d) 9,16

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Problem 10

Out of seven crystal systems how many can have body-centred unit cell?
(a) 4
(b) 2
(c) 3
(d) 5

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Problem 11

Among the following unit cells given below, which one has the highest symmetry?
(a) cubic
(b) monoclinic
(c) hexagonal
(d) orthorhombic

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Problem 12

The total elements of symmetry in a cube are
(a) 23
(b) 14
(c) 25
(d) 16

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Problem 13

In which of the following crystal systems the endcentred unit cell exists?
(a) monoclinic
(b) triclinic
(c) cubic
(d) all of these

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Problem 14

If $\mathrm{A}, \mathrm{B}, \mathrm{C}$ are unequal and $\alpha, \beta, \gamma$ are unequal and not $90^{\circ}$, it represents a
(a) triclinic system
(b) tetragonal
(c) monoclinic
(d) orthorhombic

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Problem 15

The empty space left in a hexagonal close packing of spheres in three dimensions is
(a) $64 \%$
(b) $26 \%$
(c) $14 \%$
(d) $52.4 \%$

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Problem 16

Which one of the following is not a close packed arrangement?
(a) BCC
(b) ccp
(c) hcp
(d) all of these

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Problem 17

The void formed by closed packed array of spheres located at the alternate corners of each face is
(a) octahedral void
(b) tetrahedral void
(c) triangular void
(d) both (a) and (b)

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Problem 18

What is the contribution of the atom present at the edge centre to the unit cell?
(a) $\frac{1}{8}$
(b) $\frac{1}{2}$
(c) $\frac{1}{4}$
(d) $\frac{1}{3}$

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Problem 19

The pattern of successive layers of ccp arrangement can be designated as
(a) $\mathrm{AB}, \mathrm{ABC}, \mathrm{AB}, \mathrm{ABC} \ldots$
(b) $\mathrm{AB}, \mathrm{AB}, \mathrm{AB} \ldots$
(c) $\mathrm{AB}, \mathrm{BA}, \mathrm{AB}, \mathrm{BA} \ldots$
(d) $\mathrm{BC}, \mathrm{ABC}, \mathrm{ABC} \ldots$

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Problem 20

The density of the crystal (d) is given by the formula
(a) $\frac{\mathrm{a}^{3} \mathrm{~N}_{\mathrm{A}}}{\mathrm{zM}}$
(b) $\frac{z M}{a^{3} N_{A}}$
(c) $\frac{\mathrm{N}_{\mathrm{A}} \mathrm{M}}{\mathrm{za}^{3}}$
(d) none of these

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Problem 21

In simple cubic crystal the radius ratio should be
$(\mathrm{a}) \geq 0.732$
(b) $\leq 0.732$
(c) $\leq 0.424$
$(\mathrm{d}) \leq 0.225$

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Problem 22

If $\mathrm{R}$ is the radius of the sphere in the close packed arrangement and $\mathrm{r}$ is the radius of the tetrahedral void, then
(a) $\mathrm{R}=0.414 \mathrm{r}$
(b) $\mathrm{r}=0.224 \mathrm{R}$
(c) $\mathrm{R}=0.225 \mathrm{r}$
(d) $\mathrm{r}=0.414 \mathrm{R}$

Supratim Pal

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Problem 23

The number of $\mathrm{CaF}_{2}$ units in fluorite structure is
(a) 2
(b) 1
(c) 3
(d) 4

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Problem 24

Which of the following statements about the $\mathrm{NaCl}$ crystal is correct?
(a) $\mathrm{Cl}$ ions are present at the corners and $\mathrm{Na}$ ions at the body-centre
(b) $\mathrm{Cl}^{-}$ions adopt bec arrangement
(c) $\mathrm{Cl}$ ions are packed following ABC ABC pattern of hexagonal close packing
(d) $\mathrm{Na}^{+}$ions are at the edge centres only

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Problem 25

The coordination number of $\mathrm{Zn}^{2^{+}}$and $\mathrm{S}^{2}$ ions in the zinc blende (ZnS) type structure is
(a) $6: 8$
(b) $4: 4$
(c) $4: 8$
(d) $8: 8$

Mishal Gul

Numerade Educator

Problem 26

Which among the following is likely to have Schottky defect?
(a) $\mathrm{ZnS}$
(b) $\mathrm{AgBr}$
(c) $\mathrm{NaCl}$
(d) none of these

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Problem 27

$\mathrm{ZnO}$ is white when cold and yellow when heated. It is due to the development of
(a) metal excess defect
(b) Frenkel defect
(c) Schottky defect
(d) both (b) and (c)

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Problem 28

Which of the following is not correct consequences of Schottky defect?
(a) stability of crystal decreases
(b) density decreases
(c) electrical conductivity increases
(d) lattice energy of crystal increases

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Problem 29

In Schottky defect
(a) a lattice site is occupied by electron
(b) the radius ratio, $\mathrm{r}^{+} / \mathrm{r}^{-}$, is low
(c) some of lattice sites are vacant
(d) an ion occupies interstitial position between lattice points

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Problem 30

In a closed packed array of $\mathrm{N}$ spheres, the number of tetrahedral holes are
(a) $\mathrm{N}$
(b) $2 \mathrm{~N}$
(c) $\frac{\mathrm{N}}{2}$
(d $\frac{\mathrm{N}}{4}$

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Problem 31

Which defect causes decrease in the density of a crystal?
(a) Schottky
(b) F-centre
(c) Frenkel
(d) Interstitial

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Problem 32

A crystal of $\mathrm{Fe}_{3} \mathrm{O}_{4}$ is
(a) diamagnetic
(b) ferromagnetic
(c) paramagnetic
(d) none of these

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Problem 33

Frenkel defect is noticed in
(a) $\mathrm{ZnS}$
(b) $\mathrm{AgI}$
(c) $\mathrm{AgBr}$
(d) all of these

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Problem 34

The defect when an ion occupies an interstitial position in the crystal lattice is called
(a) Schottky defect
(b) Crystal defect
(c) Frenkel defect
(d) none of these

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Problem 35

In $\mathrm{CaF}_{2}$ structure, $\mathrm{Ca}^{2}$ ions form ccp arrangement and $\mathrm{F}^{-}$ions occupy
(a) half the tetrahedral voids
(b) all tetrahedral voids
(c) half the octahedral voids
(d) all octahedral voids

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Problem 36

If the ratio of coordination number $\mathrm{P}$ to that of $\mathrm{Q}$ be $\mathrm{Y}: \mathrm{Z}$, then the formula of the solid is
(a) $\mathrm{P}_{\mathrm{Z}} \mathrm{Q}_{\mathrm{Y}}$
(b) $\mathrm{P} \mathrm{O}_{\mathrm{YZ}}$
(c) $\mathrm{P}_{1 / \mathrm{Y}} \mathrm{Q}_{1 / 2}$
(d) $\mathrm{P}_{\mathrm{Y}} \mathrm{Q}_{\mathrm{Z}}$

Mishal Gul

Numerade Educator

Problem 37

The general formula of an ionic compound crystallizing in zinc blende structure is
(a) $\mathrm{AB}_{3}$
(b) $\mathrm{AB}_{2}$
(c) $\mathrm{A}_{2} \mathrm{~B}_{2}$
(d) $\mathrm{AB}$

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Problem 38

Which of the following statements is not correct?
(a) The density of the crystal exhibiting Frenkel defect is less as compared to that of the perfect crystal
(b) The Schottky defects are more common in ionic compounds with high coordination numbers and where the sizes of ions are small
(c) In alkali halides, Frenkel defects are not found
(d) The density of the crystal exhibiting Schottky defect is less as compared to that of the perfect crystal

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Problem 39

Which of the following statements is not correct?
(a) Heating of zinc oxide leads to the formation of a yellow coloured non-stoichiometric compound
(b) The creation of cationic holes in ionic crystals imparts electrical conductivity to such crystals
(c) The compound ferrous oxide can be prepared in its stoichiometric composition
(d) Silver bromide shows both types of Schottky and Frenkel defects

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Problem 40

On heating some polar crystals, weak electric current is produced. It is termed as
(a) superconductivity
(b) piezoelectricity
(c) photoelectric current
(d) none of these

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Problem 41

Mark the correct statement
(a) CsCl crystal show Schottky defect
(b) Crystals having F-centres are coloured and paramagnetic
(c) Photo sensitivity of $\mathrm{AgBr}$ is due to the presence of Frenkel defect in its crystals
(d) all of these are correct

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Problem 42

Which substance will conduct electric current in the solid state?
(a) Diamond
(b) Graphite
(c) Sodium chloride
(d) Iodine

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Problem 43

The substance which possesses zero resistance at $0 \mathrm{~K}$ is called
(a) Super conductor
(b) Insulator
(c) Conductor
(d) Semiconductor

Narayan Hari

Numerade Educator

Problem 44

In which of the following structures, the cation has maximum coordination number?
(a) $\mathrm{NaCl}$
(b) $\mathrm{Na}_{2} \mathrm{O}$
(c) zinc blende
(d) $\mathrm{CaF}_{2}$

Narayan Hari

Numerade Educator

Problem 45

In the zinc blende structure $(\mathrm{ZnS}), \mathrm{S}^{2-}$ adopt ccp arrangement and $\mathrm{Zn}^{2+}$ occupy
(a) Alternate tetrahedral sites
(b) Octahedral sites
(c) Tetrahedral sites
(d) Both octahedral and tate 6

Narayan Hari

Numerade Educator

Problem 46

An example of ferroelectric substance is
(a) Tourmaline
(b) Quartz
(c) Barium titanate
(d) Lead zirconate

Narayan Hari

Numerade Educator

Problem 47

An example of a ferromagnetic oxide is
(a) $\mathrm{TiO}_{2}$
(b) $\mathrm{CrO}_{2}$
(c) $\mathrm{Mn}_{2} \mathrm{O}_{7}$
(d) $\mathrm{Fe}_{3} \mathrm{O}_{4}$

Mishal Gul

Numerade Educator

Problem 48

If the alignment of magnetic moments in a substance is in a compensatory way so as to give zero net magnetic moment, then the substance is said to be
(a) Anti-ferromagntic
(b) Diamagnetic
(c) Ferrimagnetic
(d) Ferromagnetic

Narayan Hari

Numerade Educator

Problem 49

Which of the following is a ferrite?
(a) $\mathrm{MgFe}_{2} \mathrm{O}_{4}$
(b) $\mathrm{Zn}_{3} \mathrm{FeO}_{4}$
(c) $\mathrm{AlFe}_{2} \mathrm{O}_{4}$
(d) $\mathrm{Na}_{2} \mathrm{Fe}_{2} \mathrm{O}_{4}$

Narayan Hari

Numerade Educator

Problem 50

An example of anti-ferroelectric substance is
(a) $\mathrm{Fe}_{3} \mathrm{O}_{4}$
(b) $\mathrm{Pb} Z \mathrm{OO}_{3}$
(c) $\mathrm{KH}_{2} \mathrm{PO}_{4}$
(d) $\mathrm{BaTiO}_{3}$

Narayan Hari

Numerade Educator

Problem 51

In a solid AB having NaCl structure, A atoms occupy the corners of the cubic unit cell. If all the facecentred atoms along one of the axes are removed, then the resultant stoichiometry of the solid is
(a) $\mathrm{AB}$
(b) $\mathrm{A}_{2} \mathrm{~B}_{2}$
(c) $\mathrm{A}_{2} \mathrm{~B}_{3}$
(d) $\mathrm{A}_{3} \mathrm{~B}_{4}^{2}$

Muhammad Ahsan

Numerade Educator

Problem 52

$\mathrm{AB} \mathrm{ABA} \ldots$. represents an arrangement of layers called
(a) cubic closed packing
(b) fluorite closed packing
(c) hexagonal closed packing
(d) body-centred cubic packing

Narayan Hari

Numerade Educator

Problem 53

$\mathrm{CaO}$ and $\mathrm{NaCl}$ have same crystal structure and nearly the same ionic radii. If $\mathrm{X}$ is the lattice energy of $\mathrm{NaCl}$, the lattice energy of $\mathrm{CaO}$ is very nealy
(a) $\mathrm{X}$
(b) $2 \mathrm{X}$
(c) $4 \mathrm{X}$
(d) $\mathrm{X} / 4$

Narayan Hari

Numerade Educator

Problem 54

Which of the following propertes of liquids is concerned with internal resistance to its flow?
(a) viscosity
(b) parachore value
(c) refractive index
(d) surface tension

Narayan Hari

Numerade Educator

Problem 55

The unit of surface tension is
(a) Joule $\mathrm{m}^{-1}$
(b) $\mathrm{N} \mathrm{m}^{-1}$
(c) $\mathrm{erg} \mathrm{cm}^{-1}$
(d) none of these

Narayan Hari

Numerade Educator

Problem 56

A drop of liquid acquires a spherical shape because of
(a) its tendency to maximize its surface area
(b) its tendency to acquire minimum surface area
(c) its viscous nature
(d) none of these

Narayan Hari

Numerade Educator

Problem 57

Liquefied metals contain
(a) metal anions only
(b) metal cations only
(c) metal kernels and mobile electrons
(d) metal atoms only

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Numerade Educator

Problem 58

Capillary cation of liquids can be explained on the basis of its
(a) surface tension
(b) resistance to flow
(c) heat of vaporization
(d) all of these

Narayan Hari

Numerade Educator

Problem 59

SI units of coefficient of viscosity are
(a) $\mathrm{kg} \mathrm{s}^{-1} \mathrm{~m}^{-2}$
(b) $\mathrm{g} \mathrm{m}^{-1} \mathrm{~s}^{-1}$
(c) $\mathrm{kg} \mathrm{m}^{-1} \mathrm{~s}^{-1}$
(d) $\mathrm{kg} \mathrm{cm}^{-1} \mathrm{~s}^{-1}$

Narayan Hari

Numerade Educator

Problem 60

Poise is a unit of
(a) viscosity
(b) vapour pressure
(c) surface tension
(d) parachore value

Narayan Hari

Numerade Educator

Problem 61

Which of the following is the correct relation between enthalpy of vaporization (Joule/mole) and boiling point of a liquid?
(a) $\Delta \mathrm{H}=1.5 \mathrm{P}_{\mathrm{b}}$
(b) $\Delta \mathrm{H}=77 \mathrm{~T}_{\mathrm{b}}$
(c) $\Delta \mathrm{H}=88 \mathrm{~T}_{\mathrm{b}}$
(d) $\Delta H=0.5 \mathrm{~T}_{\mathrm{b}}$

Narayan Hari

Numerade Educator

Problem 62

Which of the following liquid has the highest vapour pressure or is most volatile?
(a) HF (1)
(b) $\mathrm{NH}_{3}$ (1)
(c) $\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}$ (1)
(d) $\mathrm{H}_{2} \mathrm{O}$

Narayan Hari

Numerade Educator

Problem 63

The vapour pressure of the liquid depends upon
(a) the amount of liquid taken
(b) the temperature of the liquid
(c) the volume of the vessel
(d) both amount and temperature
(e) all of these

Narayan Hari

Numerade Educator

Problem 64

When a liquid is evaporated
(a) temperature of liquid decreases
(b) temperature of the liquid increases
(c) liquid molecules become more energetic
(d) both (b) and (c)

Narayan Hari

Numerade Educator

Problem 65

When a liquid is heated
(a) surface tension increases
(b) surface tension is lowered
(c) viscosity increases
(d) surface tension is not effected

Narayan Hari

Numerade Educator

Problem 66

A substance $A_{x} B_{y}$ crystallizes in a face-centred cubic (FCC) lattice in which atoms 'A' occupy each corner of the cube and atoms 'B' occupy the centres of each face of the cube. Identify the correct composition of the substance $A_{x} B_{y^{\prime}}$
(a) $\mathrm{AB}_{3}$
(b) $\mathrm{A}_{4} \mathrm{~B}_{3}$
(c) $\mathrm{A}_{3} \mathrm{~B}$
(d) composition cannot be specified

Shalini Tyagi

Numerade Educator

Problem 67

Which of the following statements is correct in context of point defects in a crystal?
(a) $\mathrm{AgCl}$ as well as $\mathrm{CaF}_{2}$ has Schottky defects
(b) AgCl as well as $\mathrm{CaF}_{2}^{-}$have anion Frenkel defects
(c) $\mathrm{AgCl}$ has cation Frenkel defects and $\mathrm{CaF}_{2}$ has Schottky defects
(d) $\mathrm{AgCl}$ has cation Frenkel defects and $\mathrm{CaF}_{2}$ has anion Frenkel defects

Narayan Hari

Numerade Educator

Problem 68

$\mathrm{NaCl}$ shows Schottky defects and $\mathrm{AgCl}$ Frenkel defects. Their electrical conductivity is due to
(a) lower coorination number of $\mathrm{NaCl}$
(b) higher coordination number of $\mathrm{AgCl}$
(c) motion of ions and not the motion of electrons
(d) motion of electrons and not the motion of ions

Narayan Hari

Numerade Educator

Problem 69

Pick out the incorrect statement:
(a) $\mathrm{NaCl}$ has $8: 8$ coordination, while $\mathrm{CsCl}$ is with $6: 6$ coordination
(b) In $\mathrm{Na}_{2} \mathrm{O}$ each oxide ion is coordinated by $8 \mathrm{Na}^{+}$ ions and each $\mathrm{Na}$ ' ion by 4 oxide ions
(c) $\mathrm{NaCl}$ structure transform to $\mathrm{CsCl}$ structure on heating
(d) In $\mathrm{CaF}_{2}$ structure, each $\mathrm{F}^{-}$ion is coordinated by $4 \mathrm{Ca}^{2}$ ions and each $\mathrm{Ca}^{4}$ ion is coordinated by $8 \mathrm{~F}$ ions

Riaz Ahmad

Other Schools

Problem 70

In which of the following pairs the cations occupy same type of site
(a) Zinc blende, $\mathrm{Na}_{2} \mathrm{O}$
(b) $\mathrm{NaCl}, \mathrm{CsCl}$
(c) $\mathrm{Na}_{2} \mathrm{O}, \mathrm{CaF}_{2}$
(d) $\mathrm{CsBr}, \mathrm{ZnS}^{2}$

Narayan Hari

Numerade Educator

Problem 71

The structure of $\mathrm{TlCl}$ is similar to $\mathrm{CsCl}$. What would be the radius ratio in TlCl?
(a) $0.225-0.414$
(b) $0.155-0.225$
(c) $0.732-1.000$
(d) $0.414-0.732$

Narayan Hari

Numerade Educator

Problem 72

If molar mass of $\mathrm{AB}$ is $95 \mathrm{~g} \mathrm{~mol}^{-1}$ and $\mathrm{a}$ is edge length, then the density of crystal structure is
(a) $\frac{4 \times 95}{a^{3} \times N_{A}}$
(b) $\frac{4 \mathrm{~N}_{\mathrm{A}}}{\mathrm{a}^{3} \times 95}$
(c) $\frac{2 \times 95}{a^{3} \times N_{4}}$
(d) $\frac{2 \mathrm{~N}_{\mathrm{A}}}{\mathrm{a}^{3} \times 95}$

Mishal Gul

Numerade Educator

Problem 73

The radius ratio $\left(\mathrm{r}^{+} / \mathrm{r}^{-}\right)$of $\mathrm{KF}$ is $0.98$. The structure of $\mathrm{KF}$ is similar to
(a) $\mathrm{NaCl}$
(b) $\mathrm{CsCl}$
(c) $\mathrm{ZnS}$
(d) both (a) and (b)

Narayan Hari

Numerade Educator

Problem 74

$\mathrm{Na}_{2} \mathrm{O}$ has antifluorite structure. In $\mathrm{Na}_{2} \mathrm{O}$, the coordination number of $\mathrm{N}^{\mathrm{a}^{+}}$and $\mathrm{O}^{2-}$ are respectively
(a) 4,4
(b) 6,6
(c) 4,8
(d) 8,8

Narayan Hari

Numerade Educator

Problem 75

The unit cell given below refer to ....... crystal system
(a) Trigonal
(b) Cubic
(c) orthorhombic
(d) tetragonal

Narayan Hari

Numerade Educator

Problem 76

AB Crystallises in a B.C.C lattice with edge length. a as 387 Pm. The distance between two oppositely charged ions in the lattice is
(a) $300 \mathrm{Pm}$
(b) $335 \mathrm{Pm}$
(c) $250 \mathrm{Pm}$
(d) $200 \mathrm{Pm}$

Narayan Hari

Numerade Educator

Problem 77

In a unit cell of a metal following six atoms are present. In this unit cell PQ is parallel to RS. Number of atoms present in this unit cell is
(a) 4
(b) 6
(c) 8
(d) 12

Mishal Gul

Numerade Educator

Problem 78

In calcium fluoride structure, the coordination numbers of calcium and fluoride ions respectively are
(a) 6 and 8
(b) 8 and 8
(c) 4 and 8
(d) 8 and 4

Narayan Hari

Numerade Educator

Problem 79

In a body-centred cubic arrangement, A ions occupy the centre while B ions occupy the corners of the cube. The formula of the solid is
(a) $\mathrm{AB}$
(b) $\mathrm{AB}_{2}$
(c) $\mathrm{A}_{2} \mathrm{~B}$
(d) $\mathrm{AB}_{3}$

Narayan Hari

Numerade Educator

Problem 80

If three elements A, B and C crystallized in cubic solid lattice with A atoms at corners, $\mathrm{B}$ atoms at cube centres and $\mathrm{C}$ atoms at the edges, the formula of the compound is
(a) $\mathrm{ABC}$
(b) $\mathrm{ABC}_{3}$
(c) $\mathrm{AB}_{3} \mathrm{C}$
(d) $\mathrm{A}_{3} \mathrm{~B}_{2} \mathrm{C}_{3}$

Narayan Hari

Numerade Educator

Problem 81

In a cubic unit cell, seven of the eight corners are occupied by atom $\mathrm{A}$ and having of faces are occupied of $\mathrm{B}$. The general formula of the substance having this type structure would be
(a) $\mathrm{A}_{7} \mathrm{~B}_{14}$
(b) $A_{14} B_{7}$
(c) $\mathrm{A}_{7} \mathrm{~B}_{24}$
(d) $\mathrm{A}_{9} \mathrm{~B}_{24}$

Narayan Hari

Numerade Educator

Problem 82

If the anions (b) form hexagonal close packing and cations (a) occupy only $2 / 3$ octahedral holes in it, then the general formula of the compound is
(a) $\mathrm{AB}_{2}$
(b) $\mathrm{A}_{2} \mathrm{~B}_{3}$
(c) $\mathrm{A}_{3} \mathrm{~B}_{3}$
(d) $\mathrm{A}_{2} \mathrm{~B}_{2}$

Muhammad Ahsan

Numerade Educator

Problem 83

In a spinel structure, oxides ions are cubical closest packed, whereas $1 / 8$ of tetrahedral holes are occupied by cations $\mathrm{A}^{2+}$ and $1 / 2$ of octahedral holes are occupied by cations $\mathrm{B}^{3}$ ions. The general formula of the compound having spinel structure is
(a) $\mathrm{AB}_{2} \mathrm{O}_{4}$
(b) $\mathrm{A}_{2} \mathrm{~B}_{2} \mathrm{O}_{4}$
(c) $\mathrm{A}_{2} \mathrm{~B}_{6} \mathrm{O}$
(d) $\mathrm{A}_{4} \mathrm{~B}_{3} \mathrm{O}$

Muhammad Ahsan

Numerade Educator

Problem 84

A solid PQR has $\mathrm{P}, \mathrm{Q}, \mathrm{R}$ wranged as shown below. The formula of the solid is
(a) PQR
(b) $\mathrm{P}_{2} \mathrm{QR}$
(c) $\mathrm{PQ}_{8} \mathrm{R}_{2}$
(d) $\mathrm{PQ}_{2} \mathrm{R}_{2}$

Riaz Ahmad

Other Schools

Problem 85

In a cubic closed packed structure of mixed oxides, the lattice is made up of oxide ions, $20 \%$ of tetrahedral Voids are occupied by divalent $\mathrm{A}^{2+}$ ions and $50 \%$ of the octahedral voids by trivalent $\mathrm{B}^{3+}$. The formula of the oxide is?
(a) $\mathrm{A}_{4} \mathrm{~B}_{5} \mathrm{O}_{10}$
(b) $\mathrm{A}_{2} \mathrm{~B}_{5} \mathrm{O}_{5}$
(c) $\mathrm{A}_{2} \mathrm{BO}$
(d) $\mathrm{A}_{4} \mathrm{~B}_{5} \mathrm{O}_{8}$

Narayan Hari

Numerade Educator

Problem 86

A compound formed by elements A and B crystallizes in cubic structure where A atoms are at the corners or a cube and $\mathrm{B}$ atoms are at the face centre. The formula of the compound is
(a) $\mathrm{AB}$
(b) $\mathrm{AB}_{2}$
(c) $\mathrm{AB}_{3}$
(d) $\mathrm{AB}_{4}$

Narayan Hari

Numerade Educator

Problem 87

The radius of $\mathrm{Ag}^{+}$ion is $126 \mathrm{pm}$ while that of $\mathrm{I}$ ion is $216 \mathrm{pm}$. The coordination number of $\mathrm{Ag}$ in $\mathrm{AgI}$ is
(a) 8
(b) 6
(c) 4
(d) 2

Narayan Hari

Numerade Educator

Problem 88

Which of the following crystals have $6: 6$ coordination?
(a) $\mathrm{MnO}$
(b) $\mathrm{NH}_{4} \mathrm{I}$
(c) $\mathrm{ZnS}$
(d) none of these

Narayan Hari

Numerade Educator

Problem 89

$\mathrm{TiO}_{2}$ (rutile) shows $6: 3$ coordination. The solid having rutile like structure among the following is
(a) $\mathrm{KCl}$
(b) $\mathrm{SnO}_{2}$
(c) $\mathrm{ZnS}$
(d) none of these

Muhammad Ahsan

Numerade Educator

Problem 90

$\mathrm{M}_{2} \mathrm{X}$ have a structure closely related to that of fluorite. It is actually reverse of fluorite structure hence called antifluorite structure. In such a structure
(a) $\mathrm{F}$ ions occupy all the 8 octahedral voids
(b) each $\mathrm{F}^{-}$is surrounded by $4 \mathrm{Ca}^{2^{+}}$in tetrahedral arrangement
(c) larger cations occupy the position of $\mathrm{F}$ - ions and smaller anions that of $\mathrm{Ca}^{2+}$ ions.
(d) smaller cations occupy the position of fluoride ions and larger anions that of $\mathrm{Ca}^{2^{+}}$ions

Narayan Hari

Numerade Educator

Problem 91

The number of atoms per unit cell in a BCC, a FCC and a simple cubic cell are respectively
(a) $1,4,2$
(b) $2,4,1$
(c) $4,1,2$
(d) $4,2,2$

Narayan Hari

Numerade Educator

Problem 92

A solid having unit cell made up of planes as shown in figure coordination number of ' $\mathrm{X}$ ' is
(a) 12
(b) 10
(c) 6
(d) 4

Riaz Ahmad

Other Schools

Problem 93

The number of atoms per unit cell in a simple cubic, face-centred cubic and body-centred cubic are....... respectively
(a) $1,2,4$
(b) $1,4,2$
(c) $4,2,1$
(d) $1,4,3$

Narayan Hari

Numerade Educator

Problem 94

Amorphous substances show
(i) short and long range order
(ii) short range order
(iii) long range order
(iv) have no sharp melting point
(a) (i) and (ii) are correct
(b) (ii) and (iv) are correct
(c) (ii), (iii) and (iv) are correct
(d) (i) and (iv) are correct

Narayan Hari

Numerade Educator

Problem 95

A compound contains two types of atoms: $\mathrm{X}$ and $\mathrm{Y}$. It crystallizes in a cubic lattice with atoms $\mathrm{X}$ at the corners of the unit cell and atoms $\mathrm{Y}$ at the body centres. The simplest possible formula of this compound is:
(a) XY
(b) $\mathrm{X}_{2} \mathrm{Y}_{2}$
(c) $\mathrm{XY}_{6}$
(d) $\mathrm{X}_{8} \mathrm{Y}$

Mishal Gul

Numerade Educator

Problem 96

Which of the following statements is correct?
(1) The coordination number of each type of ion in $\mathrm{CsCl}$ crystal is 8
(2) A metal that crystallizes in BCC structure has a coordination number of 12
(3) A unit cell of an ionic crystal shares some of its ion with other units cells
(4) the length of unit cell in $\mathrm{NaCl}$ is $552 \mathrm{pm}$ (r $\mathrm{Na}^{+}=$ $95 \mathrm{pm}, \mathrm{r} \mathrm{Cl}=181 \mathrm{pm}$ )
(a) 1,2
(b) 1,3
(c) 2,3
(d) 2,4

Mishal Gul

Numerade Educator

Problem 97

The edge length of the unit cell of $\mathrm{NaCl}$ crystal lattice is $552 \mathrm{pm}$. If the ionic radius of sodium ion is $95 \mathrm{pm}$. What is the ionic radius of chloride ion?
(a) $181 \mathrm{pm}$
(b) $190 \mathrm{pm}$
(c) $276 \mathrm{pm}$
(d) $368 \mathrm{pm}$

Narayan Hari

Numerade Educator

Problem 98

The second order Bragg diffraction of X-rays, with $\lambda=1 \AA$ from a set of parallel planes in a metal, occurs at an angle of $60^{\circ} .$ The distance between the scattering planes in the crystal is
(a) $2.00 \AA$
(b) $1.00 \AA$
(c) $0.575 \AA$
(d) $1.15 \AA$

Narayan Hari

Numerade Educator

Problem 99

The closet distance between two atoms (in terms of edge length) would be highest for which of unit cell, assuming the edge length of each unit cell of be 'a'
(a) FCC unit cell
(b) BCC unit cell
(c) diamond unit cell
(d) primitive cubic cell

Narayan Hari

Numerade Educator

Problem 100

A solid $\mathrm{X}^{4} \mathrm{Y}^{-}$has the $\mathrm{Y}^{-}$ions arranged as below. If the $\mathrm{X}^{+}$ions occupy half of the tetrahedral sites in the structure. The formula of solid is
(a) XY
(b) $\mathrm{X}_{3} \mathrm{Y}_{4}$
(c) $\mathrm{XY}_{2}$
(d) $\mathrm{X}_{2} \mathrm{Y}$

Narayan Hari

Numerade Educator

Problem 101

$\mathrm{NaCl}$ is doped with $2 \times 10^{-3} \mathrm{~mol} \% \mathrm{SrCl}_{2}$, the concen-
tration of cation vacancies is
(a) $12.04 \times 10^{18} \mathrm{~mol}^{-1}$
(b) $10.01 \times 10^{18} \mathrm{~mol}^{-1}$
(c) $12.04 \times 10^{20} \mathrm{~mol}^{-1}$
(d) $4.02 \times 10^{18} \mathrm{~mol}^{-1}$

Narayan Hari

Numerade Educator

Problem 102

A solid XY has NaCl structure. If radius of $\mathrm{X}^{+}$is 100 $\mathrm{pm}$, the radius of $\mathrm{Y}$-ion is
(a) $136.6$ to $241.6 \mathrm{pm}$
(b) $341.6$ to $134.6 \mathrm{pm}$
(c) $128 \mathrm{pm}$
(d) $136.8 \mathrm{pm}$

Narayan Hari

Numerade Educator

Problem 103

The ionic radii of $\mathrm{Rb}^{+}$and $\mathrm{I}^{-}$are $1.46 \AA$ and $2.16 \AA$ respectively. The most probable type of structure exhibited by it is
(a) $\mathrm{CaF}_{2}$ type
(b) $\mathrm{ZnS}$ type
(c) $\mathrm{CsCl}$ type
(d) $\mathrm{NaCl}$ type

Narayan Hari

Numerade Educator

Problem 104

A solid has 3 types of atoms namely $\mathrm{X}, \mathrm{Y}$ and $\mathrm{Z}$. $\mathrm{X}$ forms an FCC lattice with $\mathrm{Y}$ atoms occupying all the tetrahedral voids and $Z$ atoms occupying half the octahedral voids. The formula of the solid is
(a) XYZ
(b) $\mathrm{X}_{2} \mathrm{Y}_{4} \mathrm{Z}$
(c) $\mathrm{X}_{4} \mathrm{YZ}_{2}$
(d) $X_{4} Y_{2} Z$

Narayan Hari

Numerade Educator

Problem 105

Calculate the $\lambda$ of X-rays which give a diffraction angle $2 \theta=16.80^{\circ}$ for a crystal. (Given interplanar distance = $0.200 \mathrm{~nm} ;$ diffraction $=$ first order; $\sin 8.40^{\circ}=0.1461$ )
(a) $58.4 \mathrm{pm}$
(b) $5.84 \mathrm{pm}$
(c) $584 \mathrm{pm}$
(d) $648 \mathrm{pm}$

Narayan Hari

Numerade Educator

Problem 106

Match List I with List II and select the correct answer:
$\begin{array}{ll}\text { List I } & \text { List II }\end{array}$ $\begin{aligned}&\text { (Shape) } & \text { (Radius ratio) }\end{aligned}$
1. Planar triangle
(i) $0.732$
2. Square planar
(ii) $0.225$
3. Body-centred cubic
(iii) $0.155$
4. Tetrahedral
(iv) $0.414$ $\begin{array}{llll}1 & 2 & 3 & 4\end{array}$
(a) (iii)
(ii)
(i)
(iv)
(b) (iii)
(iv)
(i)
(ii)
(c) (ii)
(i)
(iv)
(iii)
(d) (ii)
(iv)
(iii)
(i)

Riaz Ahmad

Other Schools

Problem 107

In a compound XY, the ionic radii $\mathrm{X}^{+}$and $\mathrm{Y}$ are $88 \mathrm{pm}$ and $200 \mathrm{pm}$ respectively. What is the coordination number of $\mathrm{X}^{+}$?
(a) 4
(b) 6
(c) 8
(d) 10

Narayan Hari

Numerade Educator

Problem 108

The edge length of unit cell of a metal having molecular weight $75 \mathrm{~g} / \mathrm{mol}$ is $5 \AA$ A which crystallizes in cubic lattice. If the density is $2 \mathrm{~g} / \mathrm{cc}$ then find the radius of metal atom. $\left(\mathrm{NA}=6 \times 10^{23}\right)$. Give the answer in $\mathrm{pm}$.
(a) $116.5 \mathrm{pm}$
(b) $316.5 \mathrm{pm}$
(c) $216.5 \mathrm{pm}$
(d) $416.5 \mathrm{pm}$

Narayan Hari

Numerade Educator

Problem 109

Sodium metal crystallizes as a body-centred cubic lattice with the cell edge $4.29 \AA$. What is the radius of sodium atom?
(a) $2.371 \times 10^{-7} \mathrm{~cm}$
(b) $1.857 \times 10^{8} \mathrm{~cm}$
(c) $3.817 \times 10^{-8} \mathrm{~cm}$
(d) $7.312 \times 10^{-7} \mathrm{~cm}$

Narayan Hari

Numerade Educator

Problem 110

A metallic element crystallizes into a lattice containing a sequence of layers of ABABAB... Any packing of spheres leaves out voids in the lattice. What percentage by volume of this lattice is empty space?
(a) $26 \%$
(b) $74 \%$
(c) $50 \%$
(d) $85 \%$

Narayan Hari

Numerade Educator

Problem 111

Gold (Au) crystallizes in cubic close packed (FCC). The atomic radius of gold is $144 \mathrm{pm}$ and the atomic mass of $\mathrm{Au}=197.0 \mathrm{amu}$. The density of $\mathrm{Au}$ is
(a) $19.4 \mathrm{~g} \mathrm{~cm}^{-3}$
(b) $194 \mathrm{~g} \mathrm{~cm}^{-3}$
(c) $39.4 \mathrm{~g} \mathrm{~cm}^{-3}$
(d) $0.194 \mathrm{~g} \mathrm{~cm}^{-3}$

Narayan Hari

Numerade Educator

Problem 112

An alloy of copper, silver and gold is found to have copper constituting the ccp lattice. If silver atoms occupy the edge centres and gold is present at body centre, the alloy will have the formula
(a) $\mathrm{Cu}_{4} \mathrm{Ag}_{4} \mathrm{Au}$
(b) $\mathrm{Cu} \mathrm{Ag} \mathrm{Au}$
(c) $\mathrm{Cu}_{4} \mathrm{Ag}_{2} \mathrm{Au}$
(d) $\mathrm{Cu}_{4} \mathrm{Ag}_{3} \mathrm{Au}$

Mishal Gul

Numerade Educator

Problem 113

At room temperature, sodium crystallizes in a $\mathrm{BCC}$ lattice with the cell edge (a) $4.24 \AA$. Find the density of sodium. (Atomic wt of $\mathrm{Na}=23$ )
(a) $2.01 \mathrm{~g} / \mathrm{cm}^{3}$
(b) $1.002 \mathrm{~g} / \mathrm{cm}^{3}$
(c) $3.003 \mathrm{~g} / \mathrm{cm}^{3}$
(d) $2.004 \mathrm{~g} / \mathrm{cm}^{3}$

Narayan Hari

Numerade Educator

Problem 114

The density of solid argon is $1.65 \mathrm{~g} / \mathrm{mL}$ at $-233^{\circ} \mathrm{C}$. If the argon atom is assumed to be sphere of radius $1.54 \times$ $10^{-8} \mathrm{~cm}$, what percentage of solid argon is apprarently empty space? (Atomic wt of $\mathrm{Ar}=40$ )
(a) $32 \%$
(b) $52 \%$
(c) $62 \%$
(d) $72 \%$

Narayan Hari

Numerade Educator

Problem 115

Among the following statement(s) is /are correct?
(a) The number of nearest the neighbours in three consecutive layers in ABABAB...... Type solid is 12 .
(b) Effective number of molecules per unit cell in $\mathrm{Mg} \mathrm{Al}_{2} \mathrm{O}_{4}$ is 4
(c) The distance between a tetrahedral and octahedral
hole in MgO lattice is $\frac{\sqrt{3}}{4}$ a where $a$ is the edge
length of the cube.
(d) C-atoms are present in tetrahedral and octahedral holes in diamond.

Narayan Hari

Numerade Educator

Problem 116

Identify the correct statements.
(a) The size of octahedral site is given by $r=0.414 R$ where $\mathrm{r}$ is the radius of octahedral hole and $\mathrm{R}$ is the radius of spheres enclosing it.
(b) In CCP or HCP arrangement, there are two octahedral sites per closely packed sphere.
(c) The centres of octahedral sites lie at the mid point of the sides and at the body centre of face centred cubic unit cell.
(d) The radius of tetrahedral hole
(r) and that of spheres (R) forming it are related as $\mathrm{r}=0.155 \mathrm{R}$.

Narayan Hari

Numerade Educator

Problem 117

The correct statements regarding defects in solids are,
(a) Schottky defects affect the density of solid.
(b) Trapping of an electron in the lattice leads to the formation of $\mathrm{F}$ - center.
(c) Frenkel defect is a dislocation effect.
(d) Frenkel defect is usually favoured by a very small difference in the sizes of cation and anion.

Narayan Hari

Numerade Educator

Problem 118

What will be the distance between two nearest neighbour in primitive, fcc and bcc unit cell?
(a) For bcc, $\mathrm{d}=1.414 \mathrm{a}$
(b) For bcc, $\mathrm{d}=1.726 \mathrm{a}$
(c) For primitive, $\mathrm{d}=\mathrm{a}$
(d) For fcc, $\mathrm{d}=0.707 \mathrm{a}$

Narayan Hari

Numerade Educator

Problem 119

$\mathrm{Fe}_{3} \mathrm{O}_{4}$ has spinal structure. Which is not true about this solid?
(a) Number of $\mathrm{O}^{2-}>\mathrm{Fe}^{3+}>\mathrm{Fe}^{2+}$
(b) Coordination number of $\mathrm{Fe}^{3+}=8$ through out the unit cell.
(c) $\mathrm{Fe}^{3+}$ ions are equally distributed between octahedral and tetrahedral voids.
(d) Tetrahedral voids are equally distributed between $\mathrm{Fe}^{2+}$ and $\mathrm{Fe}^{3+}$ ions.

Narayan Hari

Numerade Educator

Problem 120

Answer the following questions in reference to the above figure.
The space lattice given in the figure refers to:
(a) fluorite structure
(b) rock salt structure
(c) spinel structure
(d) inverse spinel structure

Narayan Hari

Numerade Educator

Problem 121

Answer the following questions in reference to the above figure.
$\mathrm{O}^{2}$ - ions are present in:
(a) bec arrangement
(b) fcc arrangement
(c) simple cubic arrangement
(d) hcp arrangement

Narayan Hari

Numerade Educator

Problem 122

Answer the following questions in reference to the above figure.
The formula of the compound is:
(a) $\mathrm{ABO}_{2}$
(b) $\mathrm{A}_{2} \mathrm{BO}_{3}$
(c) $\mathrm{AB}_{2} \mathrm{O}_{4}$
(d) $\mathrm{A}_{2} \mathrm{BO}_{4}$

Riaz Ahmad

Other Schools

Problem 123

Answer the following questions in reference to the above figure.
Fraction of the total octahedral voids occupied will be
(a) $\frac{1}{2}$
(b) $\frac{1}{4}$
(c) $\frac{1}{8}$
(d) $\frac{1}{6}$

Narayan Hari

Numerade Educator

Problem 124

Answer the following questions in reference to the above figure.
$\mathrm{B}^{3+}$ and $\mathrm{A}^{2+}$ ions are present in:
(a) tetrahedral voids
(b) octahedral, tetrahedral voids
(c) tetrahedral, octahedral voids
(d) octahedral, cubic voids

Narayan Hari

Numerade Educator

Problem 125

Match the following:
$$
\begin{array}{ll}
\hline \text { Column-I } & \text { Column-II } \\
\text { (Unit cell type) } & \text { (Unit cell shapes) } \\
\hline \text { (a) Simple or Primitive } & \text { (p) Cubic } \\
\text { (b) Body centered } & \text { (q) Orthorhombic } \\
\text { (c) Face centred } & \text { (r) Tetragonal } \\
\text { (d) End centred } & \text { (s) Monoclinic } \\
& \text { (t) Triclinic } \\
\hline
\end{array}
$$

Riaz Ahmad

Other Schools

Problem 126

Match the following:
Column-I
(a) $\mathrm{RbBr} \quad \mathrm{r}_{+}=1.48 \AA, \mathrm{r}_{-}=1.95 \AA$
(b) $\mathrm{MgTe} \quad \mathrm{r}_{+}=0.65 \AA, \mathrm{r}=2.21 \AA$
(c) $\mathrm{MgO} \quad \mathrm{r}_{+}=0.65 \AA, \mathrm{r}_{-}=1.4 \AA$
(d) $\mathrm{AB} \quad \mathrm{r}_{+}=0.20 \AA, \mathrm{r}_{-}=0.9 \AA$
Column-II
(p) $\mathrm{ZnS}$ type structure
(q) $\mathrm{CsCl}$ type structure
(r) Rock salt structure
(s) Co-ordination number $=3$
(t) Crystal contains voids

Riaz Ahmad

Other Schools

Problem 127

Match the following:
$$
\begin{array}{ll}
\hline \text { Column-I (Unit cell) } & \begin{array}{l}
\text { Column-II } \\
\text { (Property) }
\end{array} \\
\hline \text { (a) Primitive cubic } & \text { (p) Packing fraction }< \\
& 0.74 \\
\text { (b) } \mathrm{FCC} & \text { (q) Octahedral void } \\
\text { (c) } \mathrm{BCC} & \text { (r) Tetrahedral void } \\
\text { (d) Primitive hexagonal } & \text { (s) Cubical void } \\
& \text { (t) Co-ordination } \\
& \text { number }<12 . \\
\hline
\end{array}
$$

Riaz Ahmad

Other Schools

Problem 128

Ice crystallizes in hexagonal lattice. At a given temperature, the density of ice is $0.92 \mathrm{gcm}^{-3}$. The volume of unit cell is $1.3 \times 10^{-22} \mathrm{~cm}^{3} .$ The number of $\mathrm{H}_{2} \mathrm{O}$
molecules per unit cell is

Narayan Hari

Numerade Educator

Problem 129

Density of Palladium (At wt. $=106.4$ ) is $12.0 \mathrm{~g} / \mathrm{cc}$. The unit cell edge length is $3.9 \times 10^{-8} \mathrm{~cm}$. The effective number of atoms in the unit cell (Avogadro number is $6 \times 10^{23}$ ) is

Narayan Hari

Numerade Educator

Problem 130

The effective contribution of the corner atom 'C' in the given unit cell of $\mathrm{ABAB} \ldots \ldots .$ type of the closest packing is $\frac{1}{\mathrm{x}}$ per unit cell. The numerical value of $\mathrm{x}$ is

Narayan Hari

Numerade Educator

Problem 131

In $\mathrm{CsCl}$ structure, the number of $\mathrm{Cs}^{+}$ions that occupy second nearest neighbor locations of a $\mathrm{Cs}^{+}$ion is

Narayan Hari

Numerade Educator

Problem 132

The hexagonal close-packed lattice can be represented by figure, if $\mathrm{C}=\mathrm{a} \sqrt{\frac{3}{3}}$. There is an atom at each corner of the unit cell and another atom which can be located by moving one third the distance along the diagonal of the rhombus base, and moving perpendicularly upward by $\mathrm{C} / 2 .$ A metal crystallizes in this lattice and has a density of $2.10 \mathrm{~g} / \mathrm{cc}$. Find out the distance between the nearest atoms in $\AA$. $(\sqrt{2}=1.4$ and $\left.\mathrm{N}_{\mathrm{A}}=6 \times 10^{23}\right)$

Riaz Ahmad

Other Schools

Problem 133

133. The cubic unit cell of aluminium has an edge length of $400 \mathrm{pm}$. Its density is $2.8 \mathrm{~g} \mathrm{~cm}^{-3}$. The number of atoms present per unit cell will be $.$ (atomic mass of $\mathrm{Al}=27$ )

Narayan Hari

Numerade Educator

Problem 134

The $\mathrm{ZnS}$ structure is cubic. The unit cell may be described as a face centered sulphide ion sub-lattice with zinc ions in the centers of alternating mini cubes made by partitioning the main cube into eight equal parts. The sum of the nearest neighbors around each $\mathrm{Zn}^{2+}$ and $\mathrm{S}^{2-}$ ion in the unit cell with be equal to

Narayan Hari

Numerade Educator

Problem 135

Number of atoms in the unit cell of $\mathrm{Na}$ (BCC type crystal) and $\mathrm{Mg}$ (FCC type crystal) are respectively [2002]
(a) 4,4
(b) 4,2
(c) 2,4
(d) 1,1

Narayan Hari

Numerade Educator

Problem 136

How many unit cells are present in a cube shaped ideal crystal of $\mathrm{NaCl}$ of mass $1.00 \mathrm{~g}$ ? [Atomic mass of $\mathrm{Na}=$ $23, \mathrm{Cl}=35.5]$
[2003]
(a) $2.57 \times 10^{21}$
(b) $6.14 \times 10^{21}$
(c) $3.28 \times 10^{21}$
(d) $1.71 \times 10^{21}$

Narayan Hari

Numerade Educator

Problem 137

What type of crystal defect is indicated in the diagram below? $\mathrm{Na}^{+}, \mathrm{Cl}^{-}, \mathrm{Na}^{+}, \mathrm{Cl}^{-}, \mathrm{Na}^{+}, \mathrm{Cl}^{-}$
$\mathrm{Cl}^{-\mathrm{Cl}} \mathrm{Na}^{+} \square \mathrm{Na}$
$\mathrm{Na}^{-} \mathrm{Cl}^{-} \square \mathrm{Cl}^{-} \mathrm{Na}^{+} \mathrm{Cl}^{-}$
$\mathrm{Cl}^{-} \mathrm{Na}^{+} \mathrm{Cl}^{-} \mathrm{Na}^{+} \square \mathrm{Na}^{+}$
(a) Frenkel defect
(b) Interstitial defect
(c) Schottky defect
(d) Frenkel and Schottky defects

Narayan Hari

Numerade Educator

Problem 138

An ionic compound has a unit cell consisting of A ions at the corners of a cube and $\mathrm{B}$ ions on the centres of the faces of the cube. The empirical formula for this compound would be $[\mathbf{2 0 0 5}]$
(a) $\mathrm{AB}$
(b) $\mathrm{A}_{2} \mathrm{~B}$
(c) $\mathrm{AB}_{3}$
(d) $\mathrm{A}_{3} \mathrm{~B}$

Narayan Hari

Numerade Educator

Problem 139

Total volume of atoms present in a face-centred cubic unit cell of a metal is ( $\mathrm{r}$ is atomic radius) [2006]
(a) $\frac{20}{3} \pi \mathrm{r}^{3}$
(b) $\frac{24}{3} \pi \mathrm{r}^{3}$
(c) $\frac{12}{3} \pi r^{3}$
(d) $\frac{16}{3} \pi \mathrm{r}^{3}$

Narayan Hari

Numerade Educator

Problem 140

In a compound, atoms of element $\mathrm{Y}$ from ccp lattice and those of element $\mathrm{X}$ occupy $2 / 3^{\text {rd }}$ oftetrahedral voids. The formula of the compound will be
$[2008]$
(a) $\mathrm{X}_{4} \mathrm{Y}_{3}$
(b) $\mathrm{X}_{2} \mathrm{Y}_{3}$
(c) $\mathrm{X}_{2} \mathrm{Y}$
(d) $\mathrm{X}_{3} \mathrm{Y}_{4}$

Narayan Hari

Numerade Educator

Problem 141

Copper crystallizes in fcc with a unit cell length of $361 \mathrm{pm}$. What is the radius of copper atom? [2009]
(a) $127 \mathrm{pm}$
(b) $157 \mathrm{pm}$
(c) $181 \mathrm{pm}$
(d) $108 \mathrm{pm}$

Narayan Hari

Numerade Educator

Problem 142

The edge length of a face centred cubic cell of an ionic substance is $508 \mathrm{pm}$. If the radius of the cation is 110 $\mathrm{pm}$, the radius of the anion is
(a) $288 \mathrm{pm}$
(b) $398 \mathrm{pm}$
(c) $618 \mathrm{pm}$
(d) $144 \mathrm{pm}$

Muhammad Ahsan

Numerade Educator

Problem 143

Percentage of free space in cubic close packed structure and in body centered packed structure are respectively $[2010]$
(a) $30 \%$ and $26 \%$
(b) $26 \%$ and $32 \%$
(c) $32 \%$ and $48 \%$
(d) $48 \%$ and $26 \%$

Narayan Hari

Numerade Educator

Problem 144

In an face centred cubic lattice, atom A occupies the corner positions and atom B occupies the face centre positions. If one atom of $\mathrm{B}$ is missing from one of the face centred points, the formula of the compound is [2011]
(a) $\mathrm{A}_{2} \mathrm{~B}_{5}$
(b) $\mathrm{AB}_{2}$
(c) $\mathrm{A}_{2} \mathrm{~B}$
(d) $\mathrm{A}_{2} \mathrm{~B}_{3}$

Narayan Hari

Numerade Educator

Problem 145

Lithium forms body centered cubic structure. The length of the side of its unit cell is $351 \mathrm{pm}$. Atomic radius of the lithium will be
(a) $75 \mathrm{pm}$
(b) $240 \mathrm{pm}$
(c) $300 \mathrm{pm}$
(d) $152 \mathrm{pm}$

Narayan Hari

Numerade Educator

Problem 146

Which of the following exists as covalent crystals in the solid state?
(a) Sulphur
(b) Phosphorus
(c) Iodine
(d) Silicon

JD

Jhamku Devi

Numerade Educator

Problem 147

Experimentally it was found that a metal oxide has formula $\mathrm{M}_{0.98} \mathrm{O} .$ Metal $\mathrm{M}$, is present as $\mathrm{M}^{2+}$ and $\mathrm{M}^{3+}$ in its oxide. Fraction of the metal which exists as $\mathrm{M}^{3+}$ would be
(a) $6.05 \%$
(b) $5.08 \%$
(c) $7.01 \%$
(d) $4.08 \%$

Muhammad Ahsan

Numerade Educator

Problem 148

CsCl crystallizes in body centred cubic lattice. if ' a' is its edge length then which of the following expression is correct:
(a) $\mathrm{r}_{\mathrm{Cs}}+\mathrm{r}_{\mathrm{cT}}=\frac{\sqrt{3}}{2} \mathrm{a}$
(b) $\mathrm{r}_{\mathrm{Cs}^{*}}+\mathrm{r}_{\mathrm{C}^{-}}=\sqrt{3} \mathrm{a}$
(c) $\mathrm{r}_{\mathrm{C} s^{+}}+\mathrm{r}_{\mathrm{c}^{-}}=3 \mathrm{a}$
(d) $\mathrm{r}_{\mathrm{C}^{+}}+\mathrm{r}_{\mathrm{C}]}=\frac{3 \mathrm{a}}{2}$

Narayan Hari

Numerade Educator

Problem 149

Sodium metal crystallizes in a body centred cubic lattice with a unit cell edge of $4.29 \AA$. The radius of sodium atom is approximately $[2015]$
(a) $1.86 \mathrm{~A}$
(b) $3.22 \AA$
(c) $5.72 \AA$
(d) $0.93 \mathrm{~A}$

Muhammad Ahsan

Numerade Educator

Problem 150

Which of the following compounds is metallic and ferromagnetic [2016]
(a) $\mathrm{CrO}_{2}$
(b) $\mathrm{VO}_{2}$
(c) $\mathrm{MnO}_{2}$
(d) $\mathrm{TiO}_{2}$

Narayan Hari

Numerade Educator