Chapter 7 Molecular shapes Flashcards
valence shell electron pair repulsion theory (VSEPR Theory)
atoms and electron groups will repel each other to maximize their spatial distance
polarity of molecules
due to differences in electronegativity
intermolecular forces
forces between atom/molecules attraction
intramolecular
covalent bonds.
as the IMF↑, boiling point, melting points >increases
viscosity, surface tension
vapor pressure decreases
dipole-dipole
attractive force between the positive and negative end of polar molecules
hydrogen bonding
a special type of dipole-dipole in which a hydrogen attached to O,N, or F is attracted to nearby electron pairs.
London dispersion forces
short live attractive forces that arise due to the constant motion of electrons
it is the only LMF for non-polar(symmetric) substance
All molecules have LDF
LDF increases with size of molecule
polarizability
the ease in which an electron cloud can be destroyed
hybridization
the combination of atomic orbitals that form new orbitals called hybrid orbitals in bonding
for hybridization
- the number of total hybrid orbitals equal the total number of atomic orbitals combined.
- the hybridization used in one that results in the lowest energy for the molecule
sigma bond, ∑
an end-to-end overlap of orbitals where the electron density increases along the internuclear axis
pi bond,π
a side-by-side overlap of orbitals where the electron density increases above/ below or in front/behind the internuclear axis
Bonds
Single, ∑
double, ∑,π
triple, ∑,π,π
hybridization of orbitals
results from interactions of electrons waves
bonding orbitals
molecular orbital that serves to hold atoms together and is lower in energy
