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What part of an atom plays the major role in bonding: - correct answer ✔✔Valence Electrons
Ceramics have mostly ______ bonding: - correct answer ✔✔Ionic
Bond strength, from strongest to weakest: - correct answer ✔✔Ionic -Covalent - Metallic -
Hydrogen
The valence electrons participating in a metallic bond: - correct answer ✔✔Disassociate from
individual atoms forming a sea of electrons around the ion cores
The valance electrons participating in a covalent bond: - correct answer ✔✔Are shared between
the atoms participating in the bond
On the graph of bonding force, the slope of the line when it crosses the x-axis is indicative of: -
correct answer ✔✔Bond Strength
Which of the following electron configurations is for an inert gas? - correct answer
✔✔1s22s22p63s23p6
What type(s) of bonding would be expected for bronze (a copper-tin alloy)? - correct answer
✔✔Metallic bonding
What type(s) of bonding would be expected for rubber? - correct answer ✔✔Covalent bonding
with some van der Waals bonding
,The rate of vacancy diffusion depends partly on the number of vacancies and activation energy
to exchange. (T/F) - correct answer ✔✔True
Abrasives are an example of a material containing polycrystals. (T/F) - correct answer ✔✔False
In the image above, if energy is the y-axis and r is the x-axis, the bold line represents the
element with the lower melting point. (T/F) - correct answer ✔✔True
Dislocations are more prevalent on planes that are closely packed. (T/F) - correct answer
✔✔True
Since single crystal materials are uniform throughout, their material properties are non-
directional (isotropic). (T/F) - correct answer ✔✔False
What is the trend in electronegativity going from left to right in the periodic table. - correct
answer ✔✔Increasing
Why are noble gases the only elements found pure in nature? - correct answer ✔✔Because
they do not need to combine with other elements to have a full outer shell.
What are some characteristics of ceramics? - correct answer ✔✔Ionic or Contently bonded,
Small thermal expansion, Brittle, Large melting temperature, Large bonding energy
What type (s) of bonding would be expected for MgCl2? - correct answer ✔✔Ionic bonding
What is the lattice parameter for an Iron BCC unit cell with an atomic radius of 0.1241 nm: -
correct answer ✔✔0.2866nm (a = 4 R / root 3)
, The atomic packing factor for aluminum with a FCC unit cell is: - correct answer ✔✔0.74
The close packed plane in a FCC unit cell is: - correct answer ✔✔(1 1 1)
A FCC unit cell has how many atoms: - correct answer ✔✔4
Interstitial sites are: - correct answer ✔✔Are the voids in-between atoms in the crystalline
structure.
The close packed plane in a BCC unit cell is - correct answer ✔✔None (no closed packed plane
for BCC)
List the point coordinates for all atoms that are associated with the BCC unit cell. Select multiple
answers. - correct answer ✔✔(1 0 1) (½ ½ ½) (0 1 1) (1 1 1) ( 0 0 1) (1 0 0) (0 0 0) (0 1 0) (1 1 0)
Explain why the properties of polycrystalline materials are most often isotropic. - correct answer
✔✔Although each individual grain in a polycrystalline material may be anisotropic, if the grains
have random orientations, then the solid aggregate of the many anisotropic grains will behave
isotropically.
Substitutional defects are: - correct answer ✔✔Point defects
Calculate the number of vacancies per cm3 in iron at 950oC. The energy for vacancy formation
is 1.08 eV/atom, and the density and atomic weight for Fe are 7.65 g/cm3 and 55.85 g/mol,
respectively: - correct answer ✔✔2.93E18 vacancies/cm3
Vacancy defects are: - correct answer ✔✔When a host atom is missing from a normally
occupied site in a crystalline structure