Chemistry 12 Chapter 1 Exemplar Solutions State Solid State Part 2

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Question 9:

Which of the following is a network solid?

(i) (Solid)

(ii)

(iii) Diamond

(iv) (Ice)

Answer: (iii)

Question 10:

Which of the following solids is not an electrical conductor?

(A)

(B)

(C)

(D)

(i) (A) only

(ii) (B) Only

(iii) (C) and (D)

(iv) (B), (C) and (D)

Answer: (iii)

Question 11:

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.

Answer: (i)

Question 12:

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

Answer: (ii)

Question 13:

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

(i)

(ii)

(iii)

(iv)

Answer: (iii)

Question 14:

Which of the following oxides shows electrical properties like metals?

(i)

(ii)

(iii)

(iv)

Answer: (iv)

Question 15:

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

(i) Molecule

(ii) Ion

(iii) Electron

(iv) Atom

Answer: (iii)

Question 16:

Graphite cannot be classified as __________.

(i) Conducting solid

(ii) Network solid

(iii) Covalent solid

(iv) Ionic solid

Answer: (iv)

Question 17:

Cations are present in the interstitial sites in __________.

(i) Frenkel defect

(ii) Schottky defect

(iii) Vacancy defect

(iv) Metal deficiency defect

Answer: (i)

Question 18:

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

Answer: (ii)

Question 19:

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

Answer: (ii)

Question 20:

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

Answer: (iv)

Question 21:

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

(i) 6

(ii) 8

(iii) 10

(iv) 12

Answer: (ii)

Question 22:

Which of the following point defects are shown by 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)

Answer: (i)

Question 23:

In which pair most efficient packing is present?

(i) and

(ii) and

(iii) and

(iv) and simple cubic cell

Answer: (ii)

Question 24:

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

(i)

(ii)

(iii)

(iv)

Answer: (iii)

Question 25:

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.

Answer: (iv)