Structure of Materials: Delve into the Atomic and Molecular Arrangements of Materials

Question 1

Which of the following is **not** a three-dimensional crystal structure?

Accepted Answer

Glassy

Answer

Body-centered cubic (BCC)

Answer

Face-centered cubic (FCC)

Answer

Hexagonal close-packed (HCP)

Question 2

What is the name of the crystal defect where a regular lattice site is unoccupied?

Accepted Answer

Vacancy

Answer

Interstitial

Answer

Dislocation

Answer

Grain boundary

Question 3

What type of chemical bond is responsible for holding atoms together in a **covalent** crystal lattice?

Accepted Answer

Covalent

Answer

Ionic

Answer

Metallic

Answer

Van der Waals

Question 4

Which crystal system is characterized by a **cubic** unit cell?

Accepted Answer

Cubic

Answer

Triclinic

Answer

Monoclinic

Answer

Orthorhombic

Question 5

Which crystal structure is characterized by a repeating, three-dimensional arrangement of atoms?

Accepted Answer

Crystalline

Answer

Amorphous

Answer

Polycrystalline

Answer

Quasicrystal

Question 6

Which of the following is NOT a point defect in a crystal structure?

Accepted Answer

Edge dislocation

Answer

Vacancy

Answer

Interstitial

Answer

Frenkel defect

Question 7

Which of the following is NOT a type of crystal structure?

Accepted Answer

Amorphous

Answer

Cubic

Answer

Hexagonal

Answer

Monoclinic

Question 8

What is the term for a defect in a crystal structure where an extra atom is present at an interstitial site?

Accepted Answer

Interstitial defect

Answer

Vacancy defect

Answer

Dislocation

Answer

Grain boundary

Question 9

Which of the following materials has an amorphous structure?

Accepted Answer

Glass

Answer

Steel

Answer

Diamond

Answer

Salt

Question 10

What is the relationship between the atomic packing factor (APF) and the density of a material?

Accepted Answer

APF is directly proportional to the density of the material

Answer

APF is inversely proportional to the density of the material

Answer

APF is a measure of the number of atoms in a unit cell

Answer

APF is a measure of the symmetry of the crystal structure

Question 11

Which of the following is NOT a crystal structure?

Accepted Answer

Liquid

Answer

Body-centered cubic

Answer

Hexagonal close-packed

Answer

Face-centered cubic

Question 12

Which type of crystal defect arises from the presence of an extra atom or ion in the crystal lattice?

Accepted Answer

Interstitial

Answer

Vacancy

Answer

Dislocation

Answer

Grain boundary

Question 13

What is the primary bonding mechanism in ionic crystals?

Accepted Answer

Ionic bonding

Answer

Covalent bonding

Answer

Metallic bonding

Answer

Van der Waals bonding

Question 14

In a body-centered cubic crystal, what is the coordination number of each atom?

Accepted Answer

8

Answer

6

Answer

12

Answer

14

Question 15

Which of the following is NOT a type of crystal structure?

Accepted Answer

Amorphous

Answer

Cubic

Answer

Hexagonal

Answer

Monoclinic

Question 16

What is the characteristic of a crystal defect called a vacancy?

Accepted Answer

An absent atom in the crystal lattice

Answer

A displaced atom from its regular position

Answer

An extra atom in the crystal lattice

Question 17

Which of the following materials has an amorphous structure?

Accepted Answer

Glass

Answer

Silicon

Answer

Salt

Answer

Diamond

Question 18

Which crystal system has three unequal axes with all angles being different?

Accepted Answer

Triclinic

Answer

Orthorhombic

Answer

Tetragonal

Answer

Monoclinic

Question 19

What is the coordination number in a face-centered cubic (FCC) crystal structure?

Accepted Answer

12

Answer

8

Answer

6

Answer

4

Question 20

What type of bonding is responsible for forming ionic crystals?

Accepted Answer

Electrostatic attraction

Answer

Covalent bonding

Answer

Metallic bonding

Answer

Van der Waals force

Question 21

Which of the following materials is predicted to have the highest melting point?

Accepted Answer

Diamond

Answer

Iron

Answer

Aluminum

Answer

Gold

Question 22

What is the term for the smallest repeating unit in a crystal that retains its symmetry?

Accepted Answer

Unit cell

Answer

Atom

Answer

Crystal

Answer

Molecule