MSE 250 EXAM 1 (1-5,9) QUESTIONS & ANSWERS
The central tenet of Materials Science and Engineering is to determine the inter-
relationships between: - Answer -Structure-Processing-Properties
The four important classes of materials relevant to this class include - Answer -
Ceramic, Metal, Polymer, Semiconductor
Which class of material is generally associated with the highest density values at room
temperature? - Answer -Metals
Which of the following is the best example of material processing?
Glassy, Amorphous, Crystalline, Extrusion - Answer -Extrusion
A material is observed to have properties such as good flexibility, low density, good
ductility, and a low electrical conductivity. Select the class of material which is best
suited for the above-mentioned material. - Answer -Polymer
Which of the following is the best related to material structure?
Glassy, Sintering, Forging, Brittle - Answer -Glassy
Materials have driven advancements in our society (fill in the blank)
Stone age ⟶ Bronze age ⟶ ____________ ⟶ Silicon age - Answer -Iron Age
For each material, fill in its material class number in the middle column of blanks
(points).
Titanium
Titania
Teflon - Answer -Metal, Ceramic, Polymer
Select the 4 quantum numbers (n, l, ml, ms) for ANY 2 electrons in the 4f state:
(CHOOSE all the options that apply)
(-4)32(-1/2)
430(1/2)
423(1/2)
43(-2)(-1/2) - Answer -430(1/2)
43(-2)(-1/2)
How many electrons can occupy orbitals with n=4, l=3? - Answer -14
How many permitted l values are there for n=4? - Answer -Four
An orbital is: - Answer -A region where the probability of finding an electron is high
, According to ________________________, no two electrons can have the same set of
n, l, ml, ms quantum numbers. - Answer -Pauli exclusion principle
Aufbau Principle - Answer -An electron occupies the lowest-energy orbital that can
receive it
Hund's Rule - Answer -states that single electrons with the same spin must occupy
each equal-energy orbital before additional electrons with opposite spins can occupy
the same orbitals
Briefly cite the main differences between ionic, covalent, and metallic: - Answer -Ionic
bonds- due to large electronegativity differences and electron transfer, strong bonding
Covalent- due to electron sharing between atoms, strong bonding
Metallic- forms electron cloud of electrons to bond, weaker bonding
Ideally speaking, bonds tend to form between two particles such that they are separated
by an equilibrium distance where ____________ net force is exerted on them, and their
overall potential energy is at a ______________. - Answer -zero, minimum
This type of bond is the only primary bond that is directionally dependent: - Answer -
Covalent
A feature of an ionic bond is that it: - Answer -is non directional
Valence electrons are most available for bonding and tend to control the following
properties: chemical, thermal, electrical, optical? - Answer -true
__________ bonds are responsible for binding atoms together within a molecule of
propane, whereas _______ bonds bind separate propane molecules together in a
condensed state (liquid or crystal) - Answer -Covalent, Van der waals
________ type of bond is the weakest among the following options:
Covalent, Ionic, Van der waals, Metallic - Answer -Van der Waals
Explain simply why hydrogen fluoride (HF) has a higher boiling temperature than
hydrogen chloride (hcl) (19.4 vs. -85°C), even though HF has a lower molecular weight -
Answer -HF has stronger bonding due to hydrogen bonding while hcl has van der waals
bonding. It is harder to break bonds of hydrogen bonding, so the boiling temperature of
HF is higher.
What is the difference between atomic structure and crystal structure? - Answer -
Atomic structure relates to the number of protons and neutrons in the nucleus of an
atom, as well as the number and probability distributions of the constituent electrons.
Crystal structure pertains to the arrangement of atoms in the crystalline solid material.
Isotropic properties are: - Answer -Direction Independent
The central tenet of Materials Science and Engineering is to determine the inter-
relationships between: - Answer -Structure-Processing-Properties
The four important classes of materials relevant to this class include - Answer -
Ceramic, Metal, Polymer, Semiconductor
Which class of material is generally associated with the highest density values at room
temperature? - Answer -Metals
Which of the following is the best example of material processing?
Glassy, Amorphous, Crystalline, Extrusion - Answer -Extrusion
A material is observed to have properties such as good flexibility, low density, good
ductility, and a low electrical conductivity. Select the class of material which is best
suited for the above-mentioned material. - Answer -Polymer
Which of the following is the best related to material structure?
Glassy, Sintering, Forging, Brittle - Answer -Glassy
Materials have driven advancements in our society (fill in the blank)
Stone age ⟶ Bronze age ⟶ ____________ ⟶ Silicon age - Answer -Iron Age
For each material, fill in its material class number in the middle column of blanks
(points).
Titanium
Titania
Teflon - Answer -Metal, Ceramic, Polymer
Select the 4 quantum numbers (n, l, ml, ms) for ANY 2 electrons in the 4f state:
(CHOOSE all the options that apply)
(-4)32(-1/2)
430(1/2)
423(1/2)
43(-2)(-1/2) - Answer -430(1/2)
43(-2)(-1/2)
How many electrons can occupy orbitals with n=4, l=3? - Answer -14
How many permitted l values are there for n=4? - Answer -Four
An orbital is: - Answer -A region where the probability of finding an electron is high
, According to ________________________, no two electrons can have the same set of
n, l, ml, ms quantum numbers. - Answer -Pauli exclusion principle
Aufbau Principle - Answer -An electron occupies the lowest-energy orbital that can
receive it
Hund's Rule - Answer -states that single electrons with the same spin must occupy
each equal-energy orbital before additional electrons with opposite spins can occupy
the same orbitals
Briefly cite the main differences between ionic, covalent, and metallic: - Answer -Ionic
bonds- due to large electronegativity differences and electron transfer, strong bonding
Covalent- due to electron sharing between atoms, strong bonding
Metallic- forms electron cloud of electrons to bond, weaker bonding
Ideally speaking, bonds tend to form between two particles such that they are separated
by an equilibrium distance where ____________ net force is exerted on them, and their
overall potential energy is at a ______________. - Answer -zero, minimum
This type of bond is the only primary bond that is directionally dependent: - Answer -
Covalent
A feature of an ionic bond is that it: - Answer -is non directional
Valence electrons are most available for bonding and tend to control the following
properties: chemical, thermal, electrical, optical? - Answer -true
__________ bonds are responsible for binding atoms together within a molecule of
propane, whereas _______ bonds bind separate propane molecules together in a
condensed state (liquid or crystal) - Answer -Covalent, Van der waals
________ type of bond is the weakest among the following options:
Covalent, Ionic, Van der waals, Metallic - Answer -Van der Waals
Explain simply why hydrogen fluoride (HF) has a higher boiling temperature than
hydrogen chloride (hcl) (19.4 vs. -85°C), even though HF has a lower molecular weight -
Answer -HF has stronger bonding due to hydrogen bonding while hcl has van der waals
bonding. It is harder to break bonds of hydrogen bonding, so the boiling temperature of
HF is higher.
What is the difference between atomic structure and crystal structure? - Answer -
Atomic structure relates to the number of protons and neutrons in the nucleus of an
atom, as well as the number and probability distributions of the constituent electrons.
Crystal structure pertains to the arrangement of atoms in the crystalline solid material.
Isotropic properties are: - Answer -Direction Independent
