Final Exam Mat. Sci

Front 1

Three most basic components of an atom

Back 1

Protons, neutrons, electrons

Front 2

An element is determined by the number of what?

Back 2

Protons

Front 3

The nucleus of an atom consists of what

Back 3

Protons and Neutrons

Front 4

How many electrons are found in the outermost shell of aluminum (Atomic number 13)?

Back 4

3

Front 5

The name ____ comes from the Greek word for "burnt earth."

Back 5

Ceramics

Front 6

The blend of two metals is called a what?

Back 6

Alloy

Front 7

What do you call a material that is hard but brittle and a good insulator?

Back 7

Ceramic

Front 8

Motors inside cars are mostly made out of what material?

Back 8

Metal

Front 9

Microchips inside computers are with with Silicon, which is an example of what?

Back 9

Semiconductor

Front 10

The outside of a modern car is made from fiberglass which a material is called a what?

Back 10

Composite

Front 11

What unit is one thousandth of a millimeter?

Back 11

Micron/Micrometer

Front 12

What unit is one millionth of a millimeter?

Back 12

Nanometer

Front 13

The space Shuttle is covered with special tiles which prevent it from burning up upon its return to the atmosphere. These tiles are what type of material?

Back 13

Ceramic

Front 14

Which of the following is the hardest material on earth?

Back 14

Diamond

Front 15

If rods of these these materials are the same size, which would be lightest?

Back 15

Aluminum

Front 16

Which precious stone, often used in jewelry, is always used in laser technology?

Back 16

Ruby

Front 17

True or False: Kevlar is a type of Plastic

Back 17

True

Front 18

Which oxide is commonly used in white paints?

Back 18

Titanium

Front 19

True or False: Ceramics are typically very hard.

Back 19

True

Front 20

______ are typically organic materials.

Back 20

Polymers

Front 21

The study of metals is called what?

Back 21

Metallurgy

Front 22

A combination of two or more metals or a metal and a nonmetal is called what?

Back 22

Metal alloy

Front 23

Simple diffusion is defined as the movement of what?

Back 23

Molecules from areas of higher concentration to areas of lower concentration

Front 24

When sugar is mixed with water, equilibrium is reached when what happens?

Back 24

The dissolved sugar molecules are evenly distributed throughout the solution

Front 25

The rate of diffusion is affected by what?

Back 25

Temperature, size of molecules, concentration gradient

Front 26

The molecules in a solid lump of sugar do not move, true or false?

Back 26

False

Front 27

True of False, Diffusion is one of the processes whereby materials are exchanged between a cell and its environment.

Back 27

True

Front 28

Atomic Number

Back 28

The number of protons in the nucleus of an atom

Front 29

Anion is a ____ charged ion produced when an atom, usually of a non-metal, accepts one or more electrons.

Back 29

Negatively

Front 30

Pauli's Exclusion Principle

Back 30

No two electrons can have the same set of four quantum numbers

Front 31

Which quantum number is a quantum number representing the energy level of an electron?

Back 31

Principal

Front 32

Isotopes are atoms of the same element that have the same number of _____ but not the same number of neutrons.

Back 32

Protons

Front 33

Steels contain _____ than 2% of Carbon, less or more?

Back 33

Less

Front 34

Avogadro's number corresponds to the number of atoms needed to create a mass in units of grams numerically equal to the atomic mass.

Back 34

Atoms

Front 35

One atom of oxygen has a mass of 16 amu, without any calculations determine the mass in grams of one mole of oxygen atoms.

Back 35

16 grams

Front 36

The outer (high-energy) electrons are valence electrons, true or False?

Back 36

Trie

Front 37

Van der Waals are what kind of bonds?

Back 37

Secondary

Front 38

The mechanical properties of metals are significantly different than those of ionic and covalent networked materials, true or false?

Back 38

True

Front 39

The transition metals have what kind of bonding?

Back 39

Mixed metallic-Covalent

Front 40

Ionic solids generally have high or low temperatures?

Back 40

High

Front 41

There are how many primary bonds?

Back 41

Three

Front 42

Which of the following is not a primary bond? Covalent, hydrogen, ionic, metallic

Back 42

Hydrogen

Front 43

When atoms release electrons they have a positive net charge and a called what?

Back 43

Cations

Front 44

Covalent bonds are very weak, true or false?

Back 44

False

Front 45

Sodium Chloride is the classic covalent material, true or False?

Back 45

False

Front 46

____ Is the fraction of the volume of a unit cell that is occupied by a "Hard Sphere"

Back 46

Atomic Packing Factor

Front 47

The atomic packing factor for FCC is what?

Back 47

0.74

Front 48

_____ Atoms are associated with each BCC unit cell?

Back 48

2

Front 49

Forr the BCC Crystal structure, each corner atom is shared among _____ unit cells?

Back 49

8

Front 50

The atomic packing factor for BCC is what?

Back 50

0.68

Front 51

For the FCC Crystal Structure, each corner atom is shared among ____ unit cells.

Back 51

8

Front 52

The equivalent of _____ atoms is contained in each HCP unit cell.

Back 52

6

Front 53

APF is the volume of the unit cell dicided by the volume of atoms in a selected unit area, true of false?

Back 53

False

Front 54

Materials that can have more than one crystal structure are called allotrpic, true or false?

Back 54

True

Front 55

The _____ is the nearest number of atoms touching a particular atom, or the number of nearest neighbors for that particular atom.

Back 55

Coordination number

Front 56

_____ grains are long, thin grains in solidified polycrystalline structures.

Back 56

Columnar

Front 57

Iron exists in ))))) crystal structures over the temperature range from room temperature to its melting point.

Back 57

Two

Front 58

Bragg's Law

Back 58

Gives the relationship among the angular positions of the reinforced diffracted beams in terms of the wavelength of the incoming Xoray radiation and of the interplanar spacing of the crystal planes

Front 59

_____ Nucleation is a liquid melt that occcurs when the metal itself provides the atoms needed to form a nuclei

Back 59

Homogeneous

Front 60

))))) Nucleation is nucleation that occurs in a liquid of the surfaces of its container, insoluble, impuruties, and other structural material that lowers the critical free energy required to form a stable nuclei

Back 60

Heterogeneous

Front 61

Continuous casting is fabricated in what?

Back 61

Cast houses

Front 62

Nuclei is small particles of a new phase formed by a phase change that can grow until the phase change is complete, true or false?

Back 62

True

Front 63

grain

Back 63

Single crystal in a polycrystalline aggregate

Front 64

Columnar grains are long, thin grains in a solidified polycrystalline structure, true or false?

Back 64

True

Front 65

To produce cast ingots with a fine grain size, grain refiners are usually added to the liquid metal before casting, true or false?

Back 65

True

Front 66

How many different main types of dislocations are there?

Back 66

2

Front 67

Dislocations are _____ imperfections?

Back 67

Line

Front 68

_____ is a single crystal in a polycrystalline aggregate.

Back 68

Grain

Front 69

Grain boundaries are _____ (what kind of dislocation?)

Back 69

surface!!!

Front 70

The displacement distance of the atoms around a dislocation are called ______ what?

Back 70

Burger's

Front 71

______ is a point imperfection in a crystal lattice where an atom is missing from an atomic site

Back 71

vacancy

Front 72

_____ solid solution is a solid solution in which solute atoms of one element can replace those of solvent atoms of another element

Back 72

Substitutional

Front 73

Crystal lattice imperfections are classified according to the geometry and shape, true or false?

Back 73

True

Front 74

There are how many types of solid solution?

Back 74

2

Front 75

Increasing the temperature of a diffusion system will decrease the diffusion rate, true or false?

Back 75

False

Front 76

Carburized steels are what kind of steels?

Back 76

Low Carbon

Front 77

Steady state diffusion in which conditions do not change with time is not commonly encountered with engineering materials, true or false>

Back 77

True

Front 78

Which one of Fick's laws does is state the rate of compositional change in the change of a concentration curve

Back 78

Second

Front 79

The error function, erf, is a mathematical function existing by agreed definition and is used in some solutions of Fick's _____

Back 79

Second

Front 80

Flux is the number of atoms or other diffusing species passing through a plane of unit area per unit time, true or false?

Back 80

True

Front 81

Interstitial diffusion is diffusion of small atoms in opposite directions, true of false?

Back 81

True

Front 82

Self Diffusion is diffusion that occurs for pure metals, true or false?

Back 82

true

Front 83

The magnitude of the diffusion coefficient D is indicative of the rate at which atoms diffuse, true or false?

Back 83

True

Front 84

Vacancy diffusion is the mechanism involves the interchange of an atom from a normal lattice position to an adjacent vacant lattice stare, true or false?

Back 84

True

Front 85

The _____ test is used to evaluate the strength of metals and alloys

Back 85

Tensile

Front 86

For metals with a thick crosss section such as plates, a _____ round specimen is commonly used.

Back 86

0.50 inch diameter

Front 87

The Young's modulus is related to the bonding strength between the atoms in a metal or alloy

Back 87

True

Front 88

The yield strength is very important value for use in engineering structural design since it is the strength at which a metal or alloy shows insignificant plastic deformation, true or false?

Back 88

False

Front 89

The yield strength is very important value for use in engineering structural design since it is the strength at which a metal or alloy shows insignificant plastic deformation, true or false?

Back 89

False

Front 90

The _____ strength is the maximum strength reached in the engineering stress-strain curve.

Back 90

Ultimate Tensile

Front 91

_____ working of metals causes a metal to be strain-hardened.

Back 91

Cold

Front 92

_____ strength is the stress a which a specific amount of strain occurs in the engineering tensile test.

Back 92

Yield

Front 93

Metals and alloys show a linear relationship between stress and strain in the elastic region of the engineering stress-strain diagram, which is described by _____'s law.

Back 93

Hooke's

Front 94

The _____ strength is the maximum strength reached in the engineering stress-strain curve.

Back 94

Ultimate Tensile

Front 95

The true stress is _____ than the engineering stress, higher or lower?

Back 95

Higher

Front 96

_____ is the first stage in the annealing process that results in removal or residual stresses and formation of low-energy dislocation configurations.

Back 96

Recovery

Front 97

_____ relationship is an empirical equation that relates the strength of a metal to its grain size.

Back 97

Hall-Petch

Front 98

Recrystallization is a process that does not depend on both temperature and time, true or false?

Back 98

False

Front 99

During plastic deformation, the number of dislocations decreases dramatically, true or false?

Back 99

False

Front 100

Recrystallization proceeds more rapidly in alloys than in pure metals, true or false?

Back 100

False

Front 101

the _____ fracture of a metal occurs after extensive plastic deformation and is characterized by slow brack propagation.

Back 101

Ductile

Front 102

The transition from brittle to ductile behavior is called a ductile to brittle translation, true or false?

Back 102

False

Front 103

The transition from brittle to ductile behavior is called a ductile to brittle translation, true or false?

Back 103

False

Front 104

_____ is a measure of the amount of energy a material can absorb before fracturing.

Back 104

Toughness

Front 105

_____ is the third stage in the annealing process in which new grains start to grow in an equiaxed manner

Back 105

Grain growth

Front 106

_____ fracture is a mode of fracture characterized by rapid crack propagation

Back 106

Brittle

Front 107

What is a graph showing the relationship between the applied stress and the number of cycles to failure in fatigue?

Back 107

SN

Front 108

Fracture toughness is the resistance of a material to fail in the presence of a flaw, true or false?

Back 108

true

Front 109

_____ is a qualitative measure of the energy required to cause fracture of a material

Back 109

toughness

Front 110

Fatigue life is the number of cycles permitted at a particular stress before a material fails by fatigue, true or false?

Back 110

True

Front 111

Larson-Miller parameter used to relate the stress, temperature, and rupture time in fatigue, true or false?

Back 111

False

Front 112

Fatigue is the weakening or the breakdown of material subject to _____.

Back 112

Cyclic

Front 113

Majority of _____ base fatigue tests are performed using fully reversed loading conditions.

Back 113

Strain

Front 114

The _____ amplitude is gernally plotted against the number of cycles to failure on a linear log scale.

Back 114

Stress

Front 115

Preexisting flaws or cracks within a material component _____ the crack initiation part of the fatigue life of a component

Back 115

Reduce

Front 116

Range of stress is the difference between the maximum and mean stresses, true of false?

Back 116

False

Front 117

_____ is a simple molecular compound that can be covalently bonded together to form a long molecular change?

Back 117

Monomer

Front 118

A _____ stereoisomer is the isomer has pendant groups of atoms randomly arrange along a vinyl polymer chain>

Back 118

Atactic

Front 119

A _____ stereoisomer is this the isomer has pendant group of atoms all on the same side of a vinyl polymer chain

Back 119

Isotactic

Front 120

______ stereoisomer is this isomer that has pendant groups of atoms regularly alternating in positions on both sides of a vinyl polymer chain

Back 120

syndiotactic

Front 121

Copolymer is a polymer chain according to two ore more types of monomeric unit, true or False

Back 121

True

Front 122

Degree of polymerization is the molecular mass of a polymer chain divided by the molecular mass of its mer, true or false?

Back 122

True

Front 123

R represents an atom or side group or side group other than hydrogen, true of false?

Back 123

True

Front 124

_____ is the chemical reaction in which high-molecular-mass molecules are formed from monomers

Back 124

Polymerization

Front 125

_____ is the formation of primary valence bonds between polymer chain molecules

Back 125

Cross-linking

Front 126

_____ is the packing of molecular chains into stereoregular arrangement with a high degree of compactness

Back 126

Crystallinity

Front 127

Injection Molding

Back 127

Heat softened plastic material is forced by a screw-drive cylinder into a relatively cool mold cavity that gives the plastic the desired shape

Front 128

Blow Molding

Back 128

A hollow tube (parison) is forced into the shape of a mold cavity by internal air pressure

Front 129

Transfer molding

Back 129

thermoset process in which the molding compound is first softened by heat in a transfer chamber and then is forced under high pressure into one or more mold cavities for final curing

Front 130

Compression Molding

Back 130

Thermoset molding process in which a molding compound is first placed in a molding cavity. Then the mold is closed and heat and pressure are applied until the material is cured

Front 131

Heat Stabilizer

Back 131

Chemical that prevents reaction between chemicals

Front 132

Plasticizer

Back 132

Chemical agent added to plastic compounds to improve flow and processibility and to reduce brittleness

Front 133

Pigment

Back 133

Particle added to a material to develop color

Front 134

Filler

Back 134

Low cost inert substance added to plastics to make them less costly

Front 135

Extrusion

Back 135

Forcing of softened plastic material through an orifice, producing a continuous product

Front 136

Thermoforming

Back 136

Converting sheets or films of polymers into useable products through heat and pressure

Front 137

Coordination number of the CsCl crystal structure

Back 137

8

Front 138

Coordination number for both cations and anions of NaCl crystal structure

Back 138

6

Front 139

Number of formula units (n')within the NaCl crystal structure is

Back 139

4

Front 140

Number of formula units (n') within the CsCl crystal structure is

Back 140

1

Front 141

Number of formula units (n') within the ZnS crystal structure is

Back 141

4

Front 142

CN is the number of equidistant nearest neighbors to an atom or ion in a unit cell of a crystal structure, true or false?

Back 142

true

Front 143

The radius ratio when the anions just touch each other and contact the central cation is called the critical _____ radius ratio

Back 143

minimum

Front 144

_____ is layered structure of carbon atoms covalently bonded to three others inside the layer

Back 144

graphite

Front 145

Ceramic materials are inorganic materials that consist of metallic and nonmetallic elements bonded together primarily by metallic bonds, true or false?

Back 145

false

Front 146

The coordination number is the number of nearest neighbors surrounding a central cation?

Back 146

True

Front 147

Dislocations are _____ imperfections

Back 147

line

Front 148

There are ____ number of primary bonds.

Back 148

3

Front 149

One would expect ____ bonding between Na+ and Cl- ions in NaCl

Back 149

Ionic

Front 150

_____ boundary is a mirror imagine misorientation of the crystal structure which is considered a surface defect

Back 150

Twin

Front 151

_____ imperfection is a point imperfection in an ionic crystal in which a cation vacancy is associated with an anion vacancy

Back 151

Schottky

Front 152

Ionic bonds are non-directional

Back 152

True

Front 153

The {111} planes in FCC metals are the planes of closest packing

Back 153

True