The number of carbon atoms per unit cell of diamond is _______.

(a)

8

(b)

6

(c)

1

(d)

4

The composition of a sample of wurtzite is Fe_0.93 O_1.00 what % of Iron present in the form of Fe³⁺?

(a)

16.05%

(b)

15.05%

(c)

18.05%

(d)

17.05%

Which of the following defects decreases the density of the crystal?

(a)

Interstitial defect

(b)

Vacancy defect

(c)

Frankel defect

(d)

None of these above

In which of the following arrangements, octahedral voids are formed?

(a)

fcc

(b)

bcc

(c)

simple cubic

(d)

hcp

Which of the following cannot be regarded as molecular solid?

(a)

Silicon carbide

(b)

AIN

(c)

Diamond

(d)

All the above

Which of the following is characteristic of ionic solids?

(a)

Very low value of electrical conductivity in the molten state

(b)

Brittie nature

(c)

Very strong forces of attractions

(d)

Anisotropic nature

An example of metal deficiency defect _______.

(a)

NaCl

(b)

AgCl

(c)

CsCl

(d)

FeS

What is the relation between diamond and graphite?

(a)

Polymorphous

(b)

Isomer

(c)

Isotope

(d)

Isomorphous

A solid with formula ABC₃ would probably have, _______.

(a)

A at body centre, B at face centres and C at corners of the cube

(b)

A at corners of cube, B at body centre, C at face centre

(c)

A at corners of hexagon, B at centres of the hexagon and C inside the hexagonal unit cell

(d)

A at corner, B at face centre, C at body centre

A binary solid A+B has a structure with B^- ions constituting the lattice and A⁺ ions occupying 25% tetrahedral holes. Formula of the solid is _______.

(a)

A₂B

(b)

AB₂

(c)

AB

(d)

AB₄

Amorphous solids have _______.

(a)

Orderly arrangement of atoms

(b)

Long range of melting point

(c)

Anisotropy

(d)

both (a) and (c)

Which one of the following crystal has 8 : 8 structure?

(a)

MgF₂

(b)

CsCl

(c)

KCl

(d)

NaCl

If 'a' is the length of unit cell, then which one is correct relationship?

(a)

For simple cubic lattice, radius of metal atom =\(\frac{a}{2}\)

(b)

For bee lattice, radius of metal atom \(=\frac { \sqrt { 3a } }{ 4 } \)

(c)

For fcc lattice, radius of metal atom \(=\frac { a }{ 2\sqrt { 2 } } \)

(d)

All of these

The empty space between the shaded balls and hollow balls as shown in the diagram is called, _______.

(a)

Hexagonal void

(b)

Octahedral void

(c)

Tetrahedral void

(d)

Double triangular void

Which of the following features is false regarding the structure of CsCI?

(a)

It has bee arrangements

(b)

Co-ordination number for each ion is 8

(c)

Number of atoms in a unit cell is 4

(d)

The radius ratio (r₊/r_-) is 0.93