Covalent Bonds Flashcards
Covalent bonding
sharing of electrons
Molecular orbitals
orbitals that extend over 2 or more atomic nuclei; as atom get closer together their electrons are attracted to the opposite nucleus and get closer until they become delocalized and occupy MOs
Bond length
the distance between nuclei of two bonded atoms
Bond energy
the energy required to break the bond, completely separating the atoms
In-phase
wave functions of electrons both have maxima in the same direction at the same time
Out-of-phase
one atomic wave function is positive while the other is negative; results in a node where electron density = 0
Bonding MO
an MO lower in energy than the original AOs; electron occupying this increases bond stability
Anti-bonding MO
an MO higher in energy than the original AOs; weakens bonds
Which MO is cylindrically symmetric?
sigma
Bond order
number of shared electron pairs between 2 atoms
How many nodes are in a pi MO?
1
Heteronuclear diatomic molecules
diatomic molecules with 2 non identical atoms
Heteronuclear diatomic MOs
if one of the MOs is closer to one of the AOs the electron density for that MO will be skewed; leads to polarity
Constructive interference
Waves add and increase amplitude; causes covalent bond
Destructive interference
Amplitudes cancel each other out
