MatSci D2

Question 1

Calculate the percentage ionic character of the bond in MgO

Answer 1

73.35%

Question 2

A type of bonding that occurs when valence electrons are shared in an extended way

Answer 2

Metallic bonding

Question 3

Atomic bonding of polymers

Answer 3

covalent

Question 4

Atomic bonding of metals

Answer 4

metallic

Question 5

Atomic bonding of ceramics

Answer 5

Ionic/mixed ionic-covalent

Question 6

Atomic bonding of molecular solids

Answer 6

Van DER waals

Question 7

Atomic bonding of semi-metals

Answer 7

Mixed covalent-metallic

Question 8

Atomic bonding of intermetallics

Answer 8

Mixed metallic-ionic

Question 9

Smallest repeating structure in a crystal

Answer 9

Unit cell

Question 10

type of solid lacks long-range order

Answer 10

Amorphous solid

Question 11

type of solid with repeated regular arrangement

Answer 11

crystalline

Question 12

The unique three-dimensional arrangement of lattice points are known as ________________ (the combination of crystal structure and crystal system)

Answer 12

Bravais Lattices

Question 14

The number of atoms per unit cell in a body-centered cubic structure is

Answer 14

2

Question 15

what kind of cubic is diamond

Answer 15

FCC

Question 16

What is the coordination number of atoms in a simple cubic structure?

Answer 16

6

Question 17

What is the coordination number of atoms in a BCC cubic structure?

Answer 17

8

Question 18

What is the coordination number of atoms in a FCC cubic structure?

Answer 18

12

Question 19

What is the coordination number of atoms in a HCP cubic structure?

Answer 19

12

Question 20

Packing factor in a simple cubic structure?

Answer 20

0.52

Question 21

Atomic Packing factor in a BCC cubic structure?

Answer 21

0.68

Question 22

Packing factor in a FCC cubic structure?

Answer 22

0.74

Question 23

Packing factor in a HCP cubic structure?

Answer 23

0.74

Question 24

No. Of atoms per cell in a simple cubic structure?

Answer 24

1

Question 25

No. Of atoms per cell in a BCC cubic structure?

Answer 25

2

Question 26

No. Of atoms per cell in a FCC cubic structure?

Answer 26

4

Question 27

No. Of atoms per cell in a HCP cubic structure?

Answer 27

2

Question 28

The defect which takes place due to imperfect packing of atoms during crystallization (or bcs of temperature) is known as

Answer 28

point defects

Question 29

The formation of cation/anion vacancy clusters such that the crystal remains electrically neutral is called

Answer 29

Schottky

Question 30

The ability of a material to absorb energy in the **plastic and elastic range**

Answer 30

thoughness

Question 31

Resistance to localized surface deformation

Answer 31

Hardness

Question 32

The ability of material to absorb energy in the elastic range

Answer 32

resilience

Question 33

Degree of plastic deformation at fracture

Answer 33

Ductility

Question 34

Maximum load-bearing capacity

Answer 34

tensile strength

Question 35

Resistance to plastic deformation

Answer 35

Yield strength

Question 36

stiffness - resistance to elastic deformation

Answer 36

modulus of elasticity

Question 37

% change in area or elongation

Answer 37

Ductility

Question 38

The maximum stress that can be sustained by a structure in tension. This is the max point in the engineering stress-strain diagram

Answer 38

Tensile strength

Question 39

This mechanical property may be expressed as either percent elongation or percent reduction in area

Answer 39

ductility

Question 40

Material's ability to stretch or deform without breaking (gold, copper, al)

Answer 40

ductility

Question 41

What is the ratio of lateral strain to axial strain

Answer 41

Poisson's ratio

Question 42

The main reason ceramics are brittle because of their

Answer 42

Ionic and covalent bonding

Question 43

What type of chemical bond is primarily found in polymers like polyethylene

Answer 43

Covalent - one of the strongest bond?

Question 44

Thermoplastics can be described as polymers that

Answer 44

Can be remelted and reshaped multiple times

Question 45

Stainless steel resists corrosion mainly because of the presence of

Answer 45

chromium

Question 46

Which factor directly affects the thermal conductivity of a metal?

Answer 46

No. Of valence electrons

Question 47

Which of the following materials typically exhibits high hardness and low ductility

Answer 47

ceramic

Question 48

Which structure type is generally stronger in a fiber - reinforced composite?

Answer 48

Anisotropic

Question 50

Different properties in every direction. This is a characteristic of composite

Answer 50

Anisotropic

Question 51

Same property in every point and direction

Answer 51

Isotropic

Question 52

What is the primary reinforcement material in carbon fiber composites?

Answer 52

Graphite

Question 53

Which metal is most commonly used as a matrix in metal matrix composites

Answer 53

aluminum

Question 55

Which process is used to **improve the mechanical properties** of metals through controlled heating and cooling

Answer 55

annealing

Question 56

Doping silicon with phosphorus results in a

Answer 56

N-type semiconductor

Question 57

In stir casting, what is added into the molten metal matrix

Answer 57

reinforcement