Chapter 1 – Solid State

Class 12 Chemistry · 68 questions · 68 with answers

Questions

Q1Multiple choice

Which of the following conditions favours the existence of a substance in the solid state?

(i)High temperature
(ii)Low temperature
(iii)High thermal energy
(iv)Weak cohesive forces

Show answer

(ii) Low temperature

Q2Multiple choice

Which of the following is not a characteristic of a crystalline solid?

(i)Definite and characteristic heat of fusion.
(ii)Isotropic nature.
(iii)A regular periodically repeated pattern of arrangement of constituent particles in the entire crystal.
(iv)A true solid

Show answer

(ii) Isotropic nature.

Q3Multiple choice

Which of the following is an amorphous solid?

(i)Graphite (C)
(ii)Quartz glass (SiO2)
(iii)Chrome alum
(iv)Silicon carbide (SiC)

Show answer

(ii) Quartz glass (SiO2)

Q4Multiple choice

Which of the following arrangements shows schematic alignment of magnetic moments of antiferromagnetic substances?

(i)
(ii)
(iii)
(iv)

Show answer

(iv)

Q5Multiple choice

Which of the following is true about the value of refractive index of quartz glass?

(i)Same in all directions
(ii)Different in different directions
(iii)Cannot be measured
(iv)Always zero

Show answer

(i) Same in all directions

Q6Multiple choice

Which of the following statement is not true about amorphous solids?

(i)On heating they may become crystalline at certain temperature.
(ii)They may become crystalline on keeping for long time.
(iii)Amorphous solids can be moulded by heating.
(iv)They are anisotropic in nature.

Show answer

(iv) They are anisotropic in nature.

Q7Multiple choice

The sharp melting point of crystalline solids is due to ___________.

(i)a regular arrangement of constituent particles observed over a short distance in the crystal lattice.
(ii)a regular arrangement of constituent particles observed over a long distance in the crystal lattice.
(iii)same arrangement of constituent particles in different directions.
(iv)different arrangement of constituent particles in different directions.

Show answer

(ii) a regular arrangement of constituent particles observed over a long distance in the crystal lattice.

Q8Multiple choice

Iodine molecules are held in the crystals lattice by ____________.

(i)london forces
(ii)dipole-dipole interactions
(iii)covalent bonds
(iv)coulombic forces

Show answer

(i) london forces

Q9Multiple choice

Which of the following is a network solid?

(i)SO2 (Solid)
(ii)I2
(iii)Diamond
(iv)H2O (Ice)

Show answer

(iii) Diamond

Q10Multiple choice

Which of the following solids is not an electrical conductor? (A) Mg (s) (B) TiO (s) (C) I2 (s) (D) H2O (s)

(i)(A) only
(ii)(B) Only
(iii)(C) and (D)
(iv)(B), (C) and (D)

Show answer

(iii) (C) and (D)

Q11Multiple choice

Which of the following is not the characteristic of ionic solids?

(i)Very low value of electrical conductivity in the molten state.
(ii)Brittle nature.
(iii)Very strong forces of interactions.
(iv)Anisotropic nature.

Show answer

(i) Very low value of electrical conductivity in the molten state.

Q12Multiple choice

Graphite is a good conductor of electricity due to the presence of __________.

(i)lone pair of electrons
(ii)free valence electrons
(iii)cations
(iv)anions

Show answer

(ii) free valence electrons

Q13Multiple choice

Which of the following oxides behaves as conductor or insulator depending upon temperature?

(i)TiO
(ii)SiO2
(iii)TiO3
(iv)MgO

Show answer

(iii) TiO3

Q14Multiple choice

Which of the following oxides shows electrical properties like metals?

(i)SiO2
(ii)MgO
(iii)SO2(s)
(iv)CrO2

Show answer

(iv) CrO2

Q15Multiple choice

The lattice site in a pure crystal cannot be occupied by _________.

(i)molecule
(ii)ion
(iii)electron
(iv)atom

Show answer

(iii) electron

Q16Multiple choice

Graphite cannot be classified as __________.

(i)conducting solid
(ii)network solid
(iii)covalent solid
(iv)ionic solid

Show answer

(iv) ionic solid

Q17Multiple choice

Cations are present in the interstitial sites in __________.

(i)Frenkel defect
(ii)Schottky defect
(iii)Vacancy defect
(iv)Metal deficiency defect 3 Solid State

Show answer

(i) Frenkel defect

Q18Multiple choice

Schottky defect is observed in crystals when __________.

(i)some cations move from their lattice site to interstitial sites.
(ii)equal number of cations and anions are missing from the lattice.
(iii)some lattice sites are occupied by electrons.
(iv)some impurity is present in the lattice.

Show answer

(ii) equal number of cations and anions are missing from the lattice.

Q19Multiple choice

Which of the following is true about the charge acquired by p-type semiconductors?

(i)positive
(ii)neutral
(iii)negative
(iv)depends on concentration of p impurity

Show answer

(ii) neutral

Q20Multiple choice

To get a n-type semiconductor from silicon, it should be doped with a substance with valence__________.

(i)2
(ii)1
(iii)3
(iv)5

Show answer

(iv) 5

Q21Multiple choice

The total number of tetrahedral voids in the face centred unit cell is __________.

(i)6
(ii)8
(iii)10
(iv)12

Show answer

(ii) 8

Q22Multiple choice

Which of the following point defects are shown by AgBr(s) crystals? (A) Schottky defect (B) Frenkel defect (C) Metal excess defect (D) Metal deficiency defect

(i)(A) and (B)
(ii)(C) and (D)
(iii)(A) and (C)
(iv)(B) and (D)

Show answer

(i) (A) and (B)

Q23Multiple choice

In which pair most efficient packing is present?

(i)hcp and bcc
(ii)hcp and ccp
(iii)bcc and ccp
(iv)bcc and simple cubic cell

Show answer

(ii) hcp and ccp

Q24Multiple choice

The percentage of empty space in a body centred cubic arrangement is ________.

(i)74
(ii)68
(iii)32
(iv)26

Show answer

(iii) 32

Q25Multiple choice

Which of the following statement is not true about the hexagonal close packing?

(i)The coordination number is 12.
(ii)It has 74% packing efficiency.
(iii)Tetrahedral voids of the second layer are covered by the spheres of the third layer.
(iv)In this arrangement spheres of the fourth layer are exactly aligned with those of the first layer.

Show answer

(iv) In this arrangement spheres of the fourth layer are exactly aligned with those of the first layer.

Q26Multiple choice

In which of the following structures coordination number for cations and anions in the packed structure will be same? –

(i)Cl ion form fcc lattice and Na+ ions occupy all octahedral voids of the unit cell. –
(ii)Ca2+ ions form fcc lattice and F ions occupy all the eight tetrahedral voids of the unit cell.
(iii)O2– ions form fcc lattice and Na+ ions occupy all the eight tetrahedral voids of the unit cell. 2– 2+
(iv)S ions form fcc lattice and Zn ions go into alternate tetrahedral voids of the unit cell.

Show answer

(i) Cl ion form fcc lattice and Na+ ions occupy all octahedral voids of the unit cell. –

Q27Multiple choice

What is the coordination number in a square close packed structure in two dimensions?

(i)2
(ii)3
(iii)4
(iv)6

Show answer

(iii) 4

Q28Multiple choice

Which kind of defects are introduced by doping?

(i)Dislocation defect
(ii)Schottky defect
(iii)Frenkel defects
(iv)Electronic defects

Show answer

(iv) Electronic defects

Q29Multiple choice

Silicon doped with electron-rich impurity forms ________.

(i)p-type semiconductor
(ii)n -type semiconductor
(iii)intrinsic semiconductor
(iv)insulator 5 Solid State

Show answer

(ii) n -type semiconductor

Q30Multiple choice

Which of the following statements is not true?

(i)Paramagnetic substances are weakly attracted by magnetic field.
(ii)Ferromagnetic substances cannot be magnetised permanently.
(iii)The domains in antiferromagnetic substances are oppositely oriented with respect to each other.
(iv)Pairing of electrons cancels their magnetic moment in the diamagnetic substances.

Show answer

(ii) Ferromagnetic substances cannot be magnetised permanently.

Q31Multiple choice

Which of the following is not true about the ionic solids?

(i)Bigger ions form the close packed structure.
(ii)Smaller ions occupy either the tetrahedral or the octahedral voids depending upon their size.
(iii)Occupation of all the voids is not necessary.
(iv)The fraction of octahedral or tetrahedral voids occupied depends upon the radii of the ions occupying the voids.

Show answer

(iv) The fraction of octahedral or tetrahedral voids occupied depends upon the radii of the ions occupying the voids.

Q32Multiple choice

A ferromagnetic substance becomes a permanent magnet when it is placed in a magnetic field becuase ________.

(i)all the domains get oriented in the direction of magnetic field.
(ii)all the domains get oriented in the direction opposite to the direction of magnetic field.
(iii)domains get oriented randomly.
(iv)domains are not affected by magnetic field.

Show answer

(i) all the domains get oriented in the direction of magnetic field.

Q33Multiple choice

The correct order of the packing efficiency in different types of unit cells is ________.

(i)fcc < bcc < simple cubic
(ii)fcc > bcc > simple cubic
(iii)fcc < bcc > simple cubic
(iv)bcc < fcc > simple cubic

Show answer

(ii) fcc > bcc > simple cubic

Q34Multiple choice

Which of the following defects is also known as dislocation defect?

(i)Frenkel defect
(ii)Schottky defect
(iii)Non-stoichiometric defect
(iv)Simple interstitial defect

Show answer

(i) Frenkel defect

Q35Multiple choice

In the cubic close packing, the unit cell has ________.

(i)4 tetrahedral voids each of which is shared by four adjacent unit cells.
(ii)4 tetrahedral voids within the unit cell.
(iii)8 tetrahedral voids each of the which is shared by four adjacent unit cells.
(iv)8 tetrahedral voids within the unit cells.

Show answer

(iv) 8 tetrahedral voids within the unit cells.

Q36Multiple choice

The edge lengths of the unit cells in terms of the radius of spheres constituting fcc,bcc and simple cubic unit cell are respectively________. 4r

(i)2 2r , , 2r 4r
(ii), 2 2r ,2r 4r
(iii)2r , 2 2r , 4r
(iv)2r , ,2 2r

Show answer

(i) 2 2r , , 2r 4r

Q37Multiple choice

Which of the following represents correct order of conductivity in solids?

(i)κ metals >> κ insulators< κsemiconductors
(ii)κmetals<< κinsulators < κsemiconductors
(iii)κmetals κsemiconductors > κinsulators = zero
(iv)κ metals < κ semiconductors > κinsulators ≠ zero

Show answer

(i) κ metals >> κ insulators< κsemiconductors

Q38Multiple correct

Which of the following is not true about the voids formed in 3 dimensional hexagonal close packed structure?

(i)A tetrahedral void is formed when a sphere of the second layer is present above triangular void in the first layer.
(ii)All the triangular voids are not covered by the spheres of the second layer.
(iii)Tetrahedral voids are formed when the triangular voids in the second layer lie above the triangular voids in the first layer and the triangular shapes of these voids do not overlap.
(iv)Octahedral voids are formed when the triangular voids in the second layer exactly overlap with similar voids in the first layer.

Show answer

(iii) Tetrahedral voids are formed when the triangular voids in the second layer lie above the triangular voids in the first layer and the triangular shapes of these voids do not overlap.

(iv) Octahedral voids are formed when the triangular voids in the second layer exactly overlap with similar voids in the first layer.

Q39Multiple correct

The value of magnetic moment is zero in the case of antiferromagnetic substances because the domains ________.

(i)get oriented in the direction of the applied magnetic field.
(ii)get oriented opposite to the direction of the applied magnetic field.
(iii)are oppositely oriented with respect to each other without the application of magnetic field.
(iv)cancel out each other’s magnetic moment. 7 Solid State

Show answer

(iii) are oppositely oriented with respect to each other without the application of magnetic field.

(iv) cancel out each other’s magnetic moment. 7 Solid State

Q40Multiple correct

Which of the following statements are not true?

(i)Vacancy defect results in a decrease in the density of the substance.
(ii)Interstitial defects results in an increase in the density of the substance.
(iii)Impurity defect has no effect on the density of the substance.
(iv)Frankel defect results in an increase in the density of the substance.

Show answer

(iii) Impurity defect has no effect on the density of the substance.

(iv) Frankel defect results in an increase in the density of the substance.

Q41Multiple correct

Which of the following statements are true about metals?

(i)Valence band overlaps with conduction band.
(ii)The gap between valence band and conduction band is negligible.
(iii)The gap between valence band and conduction band cannot be determined.
(iv)Valence band may remain partially filled.

Show answer

(i) Valence band overlaps with conduction band.

(ii) The gap between valence band and conduction band is negligible.

(iv) Valence band may remain partially filled.

Q42Multiple correct

Under the influence of electric field, which of the following statements is true about the movement of electrons and holes in a p-type semi conductor?

(i)Electron will move towards the positvely charged plate through electron holes.
(ii)Holes will appear to be moving towards the negatively charged plate.
(iii)Both electrons and holes appear to move towards the positively charged plate.
(iv)Movement of electrons is not related to the movement of holes.

Show answer

(i) Electron will move towards the positvely charged plate through electron holes.

(ii) Holes will appear to be moving towards the negatively charged plate.

Q43Multiple correct

Which of the following statements are true about semiconductors?

(i)Silicon doped with electron rich impurity is a p-type semiconductor.
(ii)Silicon doped with an electron rich impurity is an n-type semiconductor.
(iii)Delocalised electrons increase the conductivity of doped silicon.
(iv)An electron vacancy increases the conductivity of n-type semiconductor.

Show answer

(ii) Silicon doped with an electron rich impurity is an n-type semiconductor.

(iii) Delocalised electrons increase the conductivity of doped silicon.

Q44Multiple correct

An excess of potassium ions makes KCl crystals appear violet or lilac in colour since ________.

(i)some of the anionic sites are occupied by an unpaired electron.
(ii)some of the anionic sites are occupied by a pair of electrons.
(iii)there are vacancies at some anionic sites.
(iv)F-centres are created which impart colour to the crystals.

Show answer

(i) some of the anionic sites are occupied by an unpaired electron.

(iv) F-centres are created which impart colour to the crystals.

Q45Multiple correct

The number of tetrahedral voids per unit cell in NaCl crystal is ________.

(i)4
(ii)8
(iii)twice the number of octahedral voids.
(iv)four times the number of octahedral voids.

Show answer

(ii) 8

(iii) twice the number of octahedral voids.

Q46Multiple correct

Amorphous solid can also be called ________.

(i)pseudo solids
(ii)true solids
(iii)super cooled liquids
(iv)super cooled solids

Show answer

(i) pseudo solids

(iii) super cooled liquids

Q47Multiple correct

A perfect crystal of silicon (Fig. 1.1) is doped with some elements as given in the options. Which of these options show n-type semiconductors? Fig. 1.1

This question refers to a figure in the original PDF.

(i)
(ii)
(iii)
(iv)

Show answer

(i)

(iii)

Q48Multiple correct

Which of the following statements are correct?

(i)Ferrimagnetic substances lose ferrimagnetism on heating and become paramagnetic.
(ii)Ferrimagnetic substances do not lose ferrimagnetism on heating and remain ferrimagnetic.
(iii)Antiferromagnetic substances have domain structures similar to ferromagnetic substances and their magnetic moments are not cancelled by each other.
(iv)In ferromagnetic substances all the domains get oriented in the direction of magnetic field and remain as such even after removing magnetic field. 9 Solid State

Show answer

(i) Ferrimagnetic substances lose ferrimagnetism on heating and become paramagnetic.

(iv) In ferromagnetic substances all the domains get oriented in the direction of magnetic field and remain as such even after removing magnetic field. 9 Solid State

Q49Multiple correct

Which of the following features are not shown by quartz glass?

(i)This is a crystalline solid.
(ii)Refractive index is same in all the directions.
(iii)This has definite heat of fusion.
(iv)This is also called super cooled liquid.

Show answer

(i) This is a crystalline solid.

(iii) This has definite heat of fusion.

Q50Multiple correct

Which of the following cannot be regarded as molecular solid?

(i)SiC (Silicon carbide)
(ii)AlN
(iii)Diamond
(iv)I2

Show answer

(i) SiC (Silicon carbide)

(ii) AlN

(iii) Diamond

Q51Multiple correct

In which of the following arrangements octahedral voids are formed?

(i)hcp
(ii)bcc
(iii)simple cubic
(iv)fcc

Show answer

(i) hcp

(iv) fcc

Q52Multiple correct

Frenkel defect is also known as ________.

(i)stoichiometric defect
(ii)dislocation defect
(iii)impurity defect
(iv)non-stoichometric defect

Show answer

(i) stoichiometric defect

(ii) dislocation defect

Q53Multiple correct

Which of the following defects decrease the density?

(i)Interstitial defect
(ii)Vacancy defect
(iii)Frankel defect
(iv)Schottky defect

Show answer

(ii) Vacancy defect

(iv) Schottky defect

Q54Short answer

Why are liquids and gases categorised as fluids?

Show answer

The liquids and gases have a property to flow i.e. the molecules can move past and tumble over one another freely. Hence, they have been categorised as fluids.

Q55Short answer

Why are solids incompressible?

Show answer

The distance between the constituent particles (atoms, ions, molecules etc.) is very less in solids. On bringing them still closer repulsion will start between electron clouds of these particles. Hence, they cannot be brought further close to each other.

Q56Short answer

Inspite of long range order in the arrangement of particles why are the crystals usually not perfect?

Show answer

Crystals have long range repeated pattern of arrangement of constitutent particles but in the process of crystallisation some deviations from the ideal arrangement (i.e. defects) may be introduced, therefore, crystals are usually not perfect.

Q57Short answer

Why does table salt, NaCl, some times appear yellow in colour?

Show answer

Yellow colour in sodium chloride is due to metal excess defect due to which unpaired electrons occupy anionic sites. These sites are called F-centres. These electrons absorb energy from the visible region for the excitation which makes crystal appear yellow.

Q58Short answer

Why is FeO (s) not formed in stoichiometric composition?

Show answer

In the crystals of FeO, some of the Fe2+ cations are replaced by Fe3+ ions. Three Fe2+ ions are replaced by two Fe3+ ions to make up for the loss of positive charge. Eventually there would be less amount of metal as compared to stoichiometric proportion.

Q59Short answer

Why does white ZnO (s) becomes yellow upon heating?

Show answer

On heating ZnO loses oxygen according to the following reaction. heating 2+ 1 – ZnO  → Zn + O2 +2e Zn2+ ions and electrons move to interstitial sites and F-centres are created which impart yellow colour to ZnO(s).

Q60Short answer

Why does the electrical conductivity of semiconductors increase with rise in temperature?

Show answer

The gap between conduction band and valence band is small in semiconductors (Fig. 1.1), therefore, electrons from the valence band can jump to the conduction band on increasing temperature. Thus they become more conducting as the temperature increases.

Q61Short answer

Explain why does conductivity of germanium crystals increase on doping with galium.

Show answer

On doping germanium with galium some of the positions of lattice of germanium are occupied by galium. Galium atom has only three valence electrons. Therefore, fourth valency of nearby germanium atom is not satisfied. The place remains vacant. This place is deficient of electrons and is therefore Fig. 1.2 : Semi conductor called electron hole or electron vacancy. Electron from neighbouring atom comes and fills the gap, thereby creating a hole in its original position. Under the influence of electric field electrons move towards positively charged plates through these holes and conduct electricity. The holes appear to move towards negatively charged plates.

Q62Short answer

In a compound, nitrogen atoms (N) make cubic close packed lattice and metal atoms (M) occupy one-third of the tetrahedral voids present. Determine the formula of the compound formed by M and N?

Show answer

M2N3

Q63Short answer

Under which situations can an amorphous substance change to crystalline form?

Show answer

See page no. 3 of NCERT textbook for Class XII. IV. Matching Type

Q64Multiple choice

Match the defects given in Column I with the statements in given Column II. Column I Column II (i) Simple vacancy defect

(a)shown by non-ionic solids and increases density of the solid. (ii) Simple interstitial defect
(b)shown by ionic solids and decreases density of the solid. (iii) Frenkel defect
(c)shown by non ionic solids and density of the solid decreases (iv) Schottky defect
(d)shown by ionic solids and density of the solid remains the same.

Show answer

(a) shown by non-ionic solids and increases density of the solid. (ii) Simple interstitial defect

(b) shown by ionic solids and decreases density of the solid. (iii) Frenkel defect

(d) shown by ionic solids and density of the solid remains the same.

Q65Multiple choice

Match the type of unit cell given in Column I with the features given in Column II. Column I Column II (i) Primitive cubic unit cell

(a)Each of the three perpendicular edges compulsorily have the different edge length i.e; a≠b≠c. (ii) Body centred cubic unit cell
(b)Number of atoms per unit cell is one. (iii) Face centred cubic unit cell
(c)Each of the three perpendicular edges compulsorily have the same edge length i.e; a = b = c (iv) End centred orthorhombic
(d)In addition to the contribution from unit cell the corner atoms the number of atoms present in a unit cell is one. (e) In addition to the contribution from the corner atoms the number of atoms present in a unit cell is three. 11 Solid State

Show answer

(a) Each of the three perpendicular edges compulsorily have the different edge length i.e; a≠b≠c. (ii) Body centred cubic unit cell

(b) Number of atoms per unit cell is one. (iii) Face centred cubic unit cell

(c) Each of the three perpendicular edges compulsorily have the same edge length i.e; a = b = c (iv) End centred orthorhombic

(d) In addition to the contribution from unit cell the corner atoms the number of atoms present in a unit cell is one. (e) In addition to the contribution from the corner atoms the number of atoms present in a unit cell is three. 11 Solid State

Q66Multiple choice

Match the types of defect given in Column I with the statement given in Column II. Column I Column II (i) Impurity defect

(a)NaCl with anionic sites called F-centres (ii) Metal excess defect
(b)FeO with Fe3+ (iii) Metal deficiency defect
(c)NaCl with Sr2+ and some cationic sites vacant

Show answer

(a) NaCl with anionic sites called F-centres (ii) Metal excess defect

(b) FeO with Fe3+ (iii) Metal deficiency defect

Q67Multiple choice

Match the items given in Column I with the items given in Column II. Column I Column II (i) Mg in solid state

(a)p-Type semiconductor (ii) MgCl2 in molten state
(b)n-Type semiconductor (iii) Silicon with phosphorus
(c)Electrolytic conductors (iv) Germanium with boron
(d)Electronic conductors

Show answer

(a) p-Type semiconductor (ii) MgCl2 in molten state

(d) Electronic conductors

(b) n-Type semiconductor (iii) Silicon with phosphorus

Q68Multiple choice

Match the type of packing given in Column I with the items given in Column II. Column I Column II (i) Square close packing in

(a)Triangular voids two dimensions (ii) Hexagonal close packing
(b)Pattern of spheres is repeated in in two dimensions every fourth layer (iii) Hexagonal close packing in
(c)Coordination number 4 three dimensions (iv) Cubic close packing in
(d)Pattern of sphere is repeated in three dimensions alternate layers

Show answer

(a) Triangular voids two dimensions (ii) Hexagonal close packing

(b) Pattern of spheres is repeated in in two dimensions every fourth layer (iii) Hexagonal close packing in

(d) Pattern of sphere is repeated in three dimensions alternate layers