Chapter 3 Flashcards
crystalline
atoms arranged in periodic, 3D arrays
noncrystalline (amorphous)
atoms have no periodic arrangement
Ordered structures tend to be closer to the minimum bonding energy. (T or F)
True
Why is there dense packing for metals? (3)
-bonds between metals are nondirectional
-nearest neighbor is closer to lower bond energy
-high degree of shielding
Simple Cubic (SC)
centers of atoms located at the eight corners of a cube
Coordination Number
number of nearest-neighbor or touching atoms
Body-Centered Cubic Structure (BCC)
atoms located at 8 cube corners with a single atom at cube center
Face-Centered Cubic Structure (FCC)
atoms located at 8 cube corners and at the centers of the 6 faces
Factors that determine crystal structure
-relative size of ions
-maintenance of charge neutrality
bond hybridization
hybrid electron orbitals form when there is significant covalent bonding
Why do metals have high densities? (2)
-close-packing
-larger atomic masses
Ceramics and Polymers contain heavier elements. (T or F)
False, lighter elements
Polymorphism/Allotropy
two or more distinct crystal structures for the same material
Two ways to deal with excess charge
- add in more cations
- have tetrahedral form complex shapes
Glass is noncrystalline (amorphous). (T or F)
True
