Material Science OSU Quizzes 1-3 for midterm 1

chapters 1-4 from the honors course w Dr. Santala

What are elements to consider with regard to the design, production, and utilization of materials?

In-service conditions,deterioration during operation, and cost

 

Processing, structure, properties, and performance

 

Processing and performance

 

Structure, deterioration during operation, and cost

Processing, structure, properties, and performance

Classify the material as to whether it is a metal, ceramic, or polymer.

Silicon dioxide or silica (SiO₂) Ceramic

Ceramic

Compute the percent ionic character of the interatomic bonds in the compound MgCl₂. The electronegativity of Mg and Cl is 1.3 and 2.9, respectively.

39%

47%

 

68%

 

53%

47%

Which of the materials below would have delocalized electrons (i.e., electrons not bound to ion cores)?

 

FeCr

 

SiO₂

 

None of these

 

CsF

FeCr

The potential energy curve of two atoms bonding has a minimum. Why?

 

Repulsive forces are negligible.

 

The force is zero when the attractive and repulsive forces cancel out.

 

Interactions forces are negligible.

 

Attractive forces are at their maximum.

 

Forces are moderate because the atoms are attracted to each other.

The force is zero when the attractive and repulsive forces cancel out.

Why are materials with metallic bonds good conductors of heat and electricity?

 

The electrons freely move between ion cores

 

The atoms vibrate more for metals than other materials

 

Bonds are easily broken for metals

 

The electrons are tightly bound to the ion cores

 

  The electrons freely move between ion cores

Ionic bonds are formed between:

 

Atoms with large differences in their electronegativities

 

Noble gas atoms

 

Polymer chains

 

Atoms with very similar electronegativities

Atoms with large differences in their electronegativities

Electronegative elements: multiple choices correct

 

Give up electrons

 

Tend to reside in the top right side of the periodic table

 

Accept electrons

 

Do not participate in electron exchange

end to reside in the top right side of the periodic table

Accept electrons

How many electrons can occupy the p subshell (e.g., 3p)?

 

2

 

6

 

14

 

10

6

Which of the following atoms has 3 valence electrons?

 

He

 

Li

 

I

 

Bi

 

Al

Al

Which of the following compounds would most likely exhibit covalent bonding?

 

MgO

 

NaCl

 

SiC

 

LiBr

SiC

atom 2

atom 5

atom 7

atom 13

(1,0,0)

(.5,.5,0)

(1,.5,.5)

(0,1,1)

(3 2̅ 4)

(2 2 1)

 

(0 2 0)

 

(2 2̅ 1)

(2 2̅ 1)

Consider nickel (Ni) metal with an atomic radius of 0.12 nm. Ni has the FCC crystal structure. Calculate the lattice parameter in nm.

 

0.34

 

0.64

 

0.45

 

0.54

.34

 

(4 2 3)

 

(4 1 3)

 

(4 3 2)

 

(3 1 4)

 

(2 1 3)

(4 2 3)

(1 0 0)

(1 0 1)

 

(1 1 1)

 

(-1-1 0)

 

(1 1 0)

(1 1 0)

White tin (Sn) is known to crystallize into a body-centered tetragonal cell shown below. In this cell, a= b= 0.37 nm and c= 0.34 nm (c is the dimension along the z-axis). The atomic radius R=0.15 nm. The interaxial angles are all 90°. Calculate the Atomic Packing Factor.
 

0.49

 

0.61

 

0.71

 

0.55

0.61

In the BCC crystal structure atoms touch along which direction?

 

(100)

 

(110)

 

[100]

 

[110]

 

[111]

[111]

White tin (Sn) is known to crystallize into a body-centered tetragonal cell shown below. How many atoms per unit cell are there?

1

2

 

4

 

6

2

For an FCC single crystal, which crystallographic plane is close packed?

 

(100)

 

(111)

 

(110)

 

[001]

 

[110]

(111)

The coordination number of an atom in the BCC crystal structure is:

 

8

 

6

 

2

 

4

 

12

8

If you would like to study dislocations with a microscopy you would most likely use:

 

Scanning probe microscopy

 

Optical microcopy

 

Scanning electron microscopy

 

Transmission electron microscopy

Transmission electron microscopy

The equilibrium number of vacancies in a crystal structure:

 

Decreases with temperature

 

Is unpredictable with changing temperature

 

Stays constant with temperature

 

Increases with temperature

increases with temperature

An example of a three-dimensional volume defect is a:

 

Grain boundary

 

Crack

 

Screw dislocation

 

Vacancy

crack

An example of a two-dimensional interfacial defect is a:

 

Grain boundary

 

Void

 

Vacancy

 

Screw dislocation

grain boundary

An example of a one-dimensional or linear defect is:

 

A vacancy

 

A self-interstitial

 

A screw dislocation

 

An external surface

A screw dislocation

Annealing twin boundaries are usually observed in which types of metals?

 

FCC crystal structure

 

HCP crystal structure

 

BCC crystal structure

 

FCC crystal structure

Which of the following are point defects? Choose all that apply.

 

Vacancy

 

Impurity atom

 

Dislocation

 

Interstitial

Vacancy

 

Impurity atom

 

Interstitial

Which of the following is NOT one of the Hume-Rothery rules?

 

The atomic radii between the two atoms types shouldbe less than 15% different.

 

Both atom types should have similar electronegativity.

 

Both atom types must be in the same column on the periodic table.

 

The crystal structure of the two atom types should be the same.

Both atom types must be in the same column on the periodic table.

When the orientation between grains is slightly misaligned we call it:

 

Slip boundary

 

High angle grain boundary

 

Low angle grain boundary

 

Twin boundary

Low angle grain boundary