Atomic Structure and Bonding Flashcards
Why study bonding?
The type of bond allows us to explain a materials properties
Describe atomic structure
consists of a nucleus and electrons, the nucleus has protons and neutrons
Have more neutrons than protons
isotopes
The atomic number represents what
of protons and electrons
Most commonly used atomic model
Bohr Atomic Model
What kind of properties do electrons have?
wavelike and particulate properties
What determines energy level of orbital?
quantum numbers
electrons tend to
occupy the lowest available energy state
electrons available for bonding
valence electrons
order of quantum energy level
K, L, M, and N
What type of material experiences ionic bonding?
Ceramics
What type of material experiences covalent bonding
Polymers
What type of material experiences metallic bonding?
Metals
What is required for Ionic bonding
Large difference in electronegativity
Is ionic bonding directional?
no, it is nondirectional
What kind of elements bond from ionic bonding?
Metal and nonmetal
The force that drives attraction between electrons
Coulombic force (Coulombs law)
Sharing electrons with similar electronegativities
Covalent bonding
Dominate bonding between non metal atoms
Covalent
is covalent bonding directional?
Yes
Bonding that involves electron sharing and is nondirectional; valence electrons are loosely held by their parent nucleus and are attracted by surrounding nuclei
Metallic bonding
Basis of high electrical conductivity
De-localized electrons (can move freely)
Bonding that occurs without electron transfer
Secondary bonding
How can fluctuating dipoles occur?
Asymmetric electron clouds
When is melting temperature large
when the energy level is large
When is the coefficient of thermal expansion larger?
If the energy is smaller
Where does secondary bonding mostly take place?
Polymers
