States of Matter – IV

1) The co-ordination number of ions in CsCI structure is
a) 4:4
b) 6:6
c) 8:8
d) 4:8

2) CsCI structure has
a) fcc arrangement
b) bcc arrangement
c) ccp arrangement
d) hcp arrangement

3) A unit cell of CsCI consists of
a) one CsCI unit
b) two CsCI units
c) four CsCI units
d) Eight CsCI units

4) TICI has a structure similar to CsCI. The co-ordination number of is
a) 4
b) 6
c) 10
d) 8

5) The structure of the CsCI crystal is a
a) Body centred cubic lattice
b) Face centred cubic lattice
c) Octahedral
d) None of these

6)The mass of a unit cell of CsCI corresponds to
a)
b)
c)
d)

7) Which of the following will not adopt the CsCI structure?
a) CsF
b) CsBr
c) CsS
d) CsCN

8) The NaCI structure can be converted into a CsCI structure
a) by application of pressure
b) by heating to 760 K
c) both by heat and pressure
d) the conversion is not possible

9) CsCI on heating to 760 K changes into
a) Liquid
b) NaCI structure
c) ZnS structure
d) None of these

10) The co-ordination number of ions in the zinc blende (ZnS) type structure is
a) 4:4
b) 6:6
c) 8:8
d) 4:8

11) Which one of the following statements is wrong about zinc blende type structure ?
a)
b)
c) AgBr has a zinc blende type structure
d) Cuprous halides have a zinc blende type structure

12) Which of the following contain(s) a zinc blende structure?
I) CuCl II ) CuBr III) Agl
a) Only I
b) Only II
c) Only III
d) All three

13) The co-ordination number of a calcium fluoride type structure is
a) 1:2
b) 4:4
c) 4:8
d) 8:4

14) The number of molecules in a unit cell of fluorite is
a) 2
b) 4
c) 6
d) 8

15) Which among the following has 4:4 co-ordination?
I) ZnS II)CuCl III) AgL
a) Only I
b) Only I and II
c) Only II and III
d) All three

16) Out of NaCI, Zns, and CsCI, in which case do the cations form a ccp structure?
a) NaCI
b) ZnS
c) CsCI
d)

17) The structure of the crystal is
a) CsCI type
b) NaCI type
c) ZnS type
d) Antifluorite

18) The antifluorite structure is derived from a fluorite structure by
a) Heating the fluorite crystal lattice
b) Subjecting the fluorite structure to high pressure
c) Interchanging the positions of the positive and negative ions in the lattice
d) None of these

19) An example of a fluorite structure is
a) NaF
b)
c)
d)

20) An example of a non-stoichiometric compound is
a) NaF
b)
c)
d) ZnS

21) Which one of the following is a ferrite?
a)
b)
c)
d)

22) Which of the following adopts a normal spinel structure?
a) CsCI
b)
c) FeO
d)

23) In Bragg equation, n represents
a)
b)
c)
d)

24) In Bragg equation, n represents the:
a) Principal Quantum number
b) Number of atoms
c) Number of electrons
d) Order of diffraction(n=1,2..)

25) The phenomenon of X-ray diffraction was studied by
a) Planck
b) Huygen
c) Bragg
d) Becquerel

26) (h,k,l) represents:
a) Miller indices
b) Lattice parameters
c) Crystal faces
d) Crystal systems

27) Which of the following is an orthosilicate?
a)
b)
c)
d)

28) Which one of the following is a three dimensional silicate?
a) Hemimorphite
b) Beryl
c) Asbestos
d) Quartz

29) The radius of an atom of an element is 500 pm. If it crystallises as a face-centred cubic lattice, the length of the side of the unit cell is
a) 176.8 pm
b) 1154.7 pm
c) 1414 pm
d) 1000 pm.

30) Pyroxenes belong to the group of
a) Pyrosilicate
b) Ring silicates
c) Chain silicates
d) Sheet silicates

31) In silicates, Si atom has the hybridization of
a) sp
b)
c)
d)

32) Ionic solids with Schottky defects contain
a) an equal number of cation and anion vacancies
b) equal anion vacancies and interstitial anions
c) Cation vacancies
d) Cation vacancies and interstitial cations

33) At zero Kelvin, most ionic crystals possess
a) Frenkel defect
b) Schottky defect
c) Metal excess defect
d) No defect

34) In stoichiometric defects, the ratio of positive and negative ions as indicated by chemical formula of the compound:
a) decreases
b) increases
c) remains the same
d) cannot be predicted

35) In the Schottky defect
a) cations are missing from the lattice sites and occupy the interstitial sites
b) an equal number of cations and anions are missing
c) Anions are missing and electrons are present in their place
d) an equal number of extra cations and electrons are present in the interstitial sites

36) As a result of the Schottky defect,
a) there is no effect on the density
b) the density of the crystal increases
c) the density of the crystal decreases
d) any of the above three can happen

37) A Schottky defect is observed in the crystal of
a) NaCI
b) TICI
c) AgCI
d)

38) Choose the correct statements out of I,II and III
I) A Schottky defect lowers the density II) A Frenkel defect increases the dielectric constant of the crystals III) Stoichiometric defects make the crystals good electrical conductors
a) I and II only
b) II and III only
c) III and I only
d) I,II and III

39) Which of these shows the Frenkel defect ?
I) AgBr II) Agl III) Zn
a) I and II only
b) II and III only
c) I and III only
d) All three

40) Frenkel defect is found in crystals in which the radius ratio is:
a) low
b) 1.3
c) 1.5
d) slightly less than unity

41) As a result of the Frenkel defect,
a) there is no effect on the density
b) there is no effect on the conductivity
c) there is no effect on the dielectric constant
d) there is no effect on all the three above

42) F-centres in an ionic crystal are
a) Lattice sites containing electrons
b) Interstitial sites containing electrons
c) Lattice sites that are vacant
d) Interstitial sites containing cations

43) Which of the following statements I – II about F-centres is/are correct ?  I) Electrons are held in the voids of crystals II)F-centres impart colour to the crystal  III) The conductivity of the crystal increases due to F-centres
a) I and II only
b) II and III only
c) I and III only
d) All three

44) A non-stoichiometric metal deficiency is shown in the salts of
a) all metals
b) alkali metals only
c) alkaline earth metals only
d) transition metals only

45) Silicon doped with arsenic is a/an
a) p-type semiconductor
b) n-type semiconductor
c) like a metallic conductor
d) an insulator

46) The doping of silicon with P or AI increases the conductivity. The difference in the two cases is that
a) P is non-metal whereas AI is a metal
b) P is a poor conductor while AI is a conductor
c) P gives rise to extra electrons while AI gives rise to holes
d) P gives rise to holes while AI gives rise to extra electrons

47) ZnO is white when cold and yellow when heated. This is due to the development of
a) Frenkel defects
b) Schottky defects
c) Metal excess defects
d) Metal deficiency defects

48) When an NaCI crystal is doped with , the nature of the defect produced is
a) interstitial defect
b) Schottky defect
c) Frenkel defect
d) none of these

49) Which of the following statements is incorrect?
a) CsCI crystal shows a Schottky defect
b) Crystals with F-centres are coloured and paramagnetic
c) The photo sensitivity of AgBr is due to the presence of a Frenkel defect in its crystals
d) None of these

50) Solid NaCI is a bad conductor of electricity since
a) In solid NaCI there are no ions
b) Solid NaCI is covalent
c) In solid NaCI ionic mobility is low
d) In solid NaCI there are no electrons

51) Which one of the following statements is wrong?
a) The conductivity of metals decreases with an increase in temperature
b) The conductivity of semiconductors increases with an increase in temperature
c) There are no superconductors at room temperature
d) Ionic solids conduct electricity due to the presence of ions

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

53) A metal has bcc structure and the edge length of its unit cell is . The volume of the unit cell in will be
a)
b)
c)
d)

54) An oxide of a transition metal that has a conductivity as well as an appearance like that of copper is
a)
b)
c)
d)

55) The oxide that is an insulator is
a) VO
b) CoO
c)
d)

56) Molten sodium chloride conducts electricity due to the presence of
a) free electrons
b) free ions
c) free molecules
d) atoms of sodium and chlorine

57) Silicon is a
a) Conductor
b) Semiconductor
c) Nonconductor
d) Metal complex

58) Which of the following oxides of chlorine is paramagnetic?
a)
b)
c)
d)

59) Select the paramagnetic ion:
a)
b)
c)
d)

60) Which of the following species is not paramagnetic?
a) NO
b)
c)
d) None of the above

61) Which of the following is not diamagnetic?
a)
b)
c)
d) All are diamagnetic

62) Ferromagnetic substances have a
a) zero magnetic moment
b) small magnetic moment
c) Large magnetic moment
d) Magnetic moment ranging from small to large

63) Ferromagnetism is maximum in
a) Fe
b) Ni
c) Co
d) Cu

64) Anti-ferromagnetic substances possess a
a) low magnetic moment
b) large magnetic moment
c) zero magnetic moment
d) any value of magnetic moment

65) Which substance shows antiferromagnetism?
a)
b) CdO
c)
d)

66) The electricity produced on applying stress on the crystals is called
a) Pyroelectricity
b) Piezoelectricity
c) Ferroelectricity
d) Anti-ferroelectricity

67) Crystals where dipoles may align themselves in an ordered manner so that there is a net dipole moment exhibit
a) Pyro-electricity
b) Piezo-electricity
c) Ferro-electricity
d) Antiferro-electricity

68) On heating some polar crystals, a weak electric current is produced. It is termed
a) piezoelectricity
b) pyroelectricity
c) photoelectric current
d) superconductivity

69) Piezoelectric crystals are used in
a) Radios
b) TVs
c) Record players
d) Refrigerators

70) Which one among the following is an example of a ferroelectric substance?
a) Quartz
b) Lead chromate
c) Barium titanate
d) Rochelle salt

71) The substance which possesses zero resistance at 0 K is called a/an
a) Conductor
b) Super conductor
c) Insulator
d) Semiconductor

72) The phenomenon of superconductivity was first discovered by
a) Einstein
b) Soddy
c) Hund and Mulliken
d) Kammerlingh Onnes.

73) Which substance acts as a superconductor at 4K?
a) Hg
b) Cu
c) Na
d) Mg

74) Compounds with identical crystal structures and analogous chemical formulae are called
a) Isomorphous
b) Allotropes
c) Isomers
d) Isotones

75) Which of the following pairs is isomorphous?
a)
b)
c)
d)

76) In a crystal, the atoms are located at the position of
a) Maximum P.E
b) Minimum P.E
c) Zero P.E
d) Infinite P.E

77) Of the following crystal lattices, the one that has the largest packing fraction is
a) Body centred cubic
b) Simple cubic
c) Simple tetragonal
d) Face centred cubic

78) Glass is a
a) Super cooled liquid
b) Metallic crystal
c) Molecular crystal
d) Covalent crystal

79) Select the correct statement from the following:
a) A cubic close packed structure has eight tetrahedral and six octahedral interstices
b) Graphite has a three dimensional crystal lattice
c) Diamond has a two dimensional crystal lattice
d) font face=”Arial”>The coordination number of a body centred cubic lattice is eight.

80) For the various types of interactions the correct order of increasing strength is
a) Covalent < hydrogen bonding < van der Waal’s < dipole-dipole
b) van der Waal’s < hydrogen bonding < dipole-dipole < covalent
c) van der Waal’s < dipole-dipole < hydrogen bonding < covalent
d) Dipole-dipole < van der Waal’s < hydrogen bonding < covalent.

81) A crystal may have one or more planes and one or more axes of symmetry but it has
a) Two centres of symmetry
b) One centre of symmetry
c) No centre of symmetry
d) None of the above

82) Which compound has the largest lattice energy?
a) LiBr
b) LiCl
c) Lil
d) LiF

83) The edge length of a face centred unit cubic cell is 508 pm. If the radius of the cation is 110 pm, the radius of the anion is
a) 144 pm
b) 288 pm
c) 618 pm
d) 398 pm

84) The layers of carbon atoms in graphite are held together by
a) coordinate covalent bonds
b) covalent bonds
c) van der Waal’s forces
d) double bonds

85) The type of bonding in ice is
a) hydrogen bonding
b) covalent bonding
c) van der Waal’s forces
d) metallic bonding

86) Germanium is an example of
a) An intrinsic semiconductor
b) An n-type semiconductor
c) A p-type semiconductor
d) an insulator

87) Which one of the following is a two dimensional covalent solid?
a) graphite
b) quartz
c) carborundum
d) pure germanium

88) When n- and p-type semiconductors are allowed to come into contact
a) Some electrons will flow from n to p
b) Some electrons will flow from p to n
c) The impurity element will flow from n to p
d) The impurity element will flow from p to n

89) In which of the following substances is the carbon atom arranged in a tetrahedral structure?
a) Diamond
b) Benzene
c) Graphite
d) Carbon black

90) Of the values required to calculate a lattice energy using the Born-Haber cycle, the one that is most difficult to measure is
a) The electron affinity of the non-metal
b) The heat of formation of gaseous atoms of the non-metal
c) The ionisation energy of the metal
d) The heat of sublimation of metal

91) Rhombic sulphur has the following structure:
a) Open chain
b) Tetrahedral
c) Puckered 6-membered ring
d) Puckered 8-membered ring

92) The density of KBr is . The length of the unit cell is 654 pm. Atomic mass of K=39, Br=80. Then the solid is
a) Face centred cubic
b) Simple cubic system
c) Body centred cubic system
d) None of these

93) The interparticle forces in solid hydrogen are
a) hydrogen bonds
b) covalent bonds
c) co-ordinate bonds
d) van der Waal’s forces

94) The total number of threefold axes of symmetry in ccp arrangement is
a) 6
b) 4
c) 2
d) 1

95) Which of the following crystals has the largest lattice energy?
a) KCI
b) MgO
c) LiBr
d) BaF

96) The low solubility of in water can be attributed to a
a) High lattice energy
b) High hydration energy
c) High molecular mass
d) All the above

97) Ionic solids are characterized by
a) Good conductivity in solid state
b) High vapour pressure
c) Low melting point
d) Solubility in polar solvents

98) A pressure cooker reduces cooking time because
a) the heat is more easily distributed
b) the higher pressure tenderizes the food
c) the boiling point of the water inside is elevated
d) a large flame is used

99) How many ions are there around the ion in NaCI crystal?
a) 3
b) 4
c) 6
d) 8

100) The liquid is in equilibrium with its vapours at its boiling point. On the average, the molecules in the two phases have equal
a) Potential energy
b) Total energy
c) Kinetic energy
d) Intermolecular forces


Answer

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