MSE 2090 Exam 1 Questions and
Answers
r0 = Equilibrium spacing - ANSWER-when -dE/dt = 0
covalent bond - ANSWER-E shared locally
Metallic bonding - ANSWER-E shared globally
Secondary bonding - ANSWER-Van der waals, physical bond weaker, permanent
dipole amd fluctuating
No directional bond - ANSWER-In metals, shares same bond with nearest neighbors
equally on all sides
Directional bonding - ANSWER-Covalent bonds w internuclear force directions
Why is H bonding so much stronger? - ANSWER-Basically an unshielded proton in
space, so it has strong interactions
Lattice - ANSWER-Where points are
Basis - ANSWER-Group of 1 or more atoms at a lattice point
Why form a solid - ANSWER-That ordered arrangement minimizes energy for those
atoms
Coordination no - ANSWER-No of nearest neighbor atoms
Allotropes (polymorphs) - ANSWER-Two or more crystal structures for the same
material
Anisotropic - ANSWER-Properties vary w direction, polycrystal that is nontextured (has
random orientation)
Isotropic - ANSWER-Properties independent of direction; poly crystal w random
orientation
Microstructure - ANSWER-Crystal structure and array of all defects, controls all
prperties, tailoring this is how materials are designed
Alloy - ANSWER-A mixture of two or more elements
Answers
r0 = Equilibrium spacing - ANSWER-when -dE/dt = 0
covalent bond - ANSWER-E shared locally
Metallic bonding - ANSWER-E shared globally
Secondary bonding - ANSWER-Van der waals, physical bond weaker, permanent
dipole amd fluctuating
No directional bond - ANSWER-In metals, shares same bond with nearest neighbors
equally on all sides
Directional bonding - ANSWER-Covalent bonds w internuclear force directions
Why is H bonding so much stronger? - ANSWER-Basically an unshielded proton in
space, so it has strong interactions
Lattice - ANSWER-Where points are
Basis - ANSWER-Group of 1 or more atoms at a lattice point
Why form a solid - ANSWER-That ordered arrangement minimizes energy for those
atoms
Coordination no - ANSWER-No of nearest neighbor atoms
Allotropes (polymorphs) - ANSWER-Two or more crystal structures for the same
material
Anisotropic - ANSWER-Properties vary w direction, polycrystal that is nontextured (has
random orientation)
Isotropic - ANSWER-Properties independent of direction; poly crystal w random
orientation
Microstructure - ANSWER-Crystal structure and array of all defects, controls all
prperties, tailoring this is how materials are designed
Alloy - ANSWER-A mixture of two or more elements
