Physical Properties of some functional groups: Intermolecular forces and water solubility
The strength of intermolecular forces in molecules with functional groups depends on:
polarity
capability of hydrogen bonding
Organic molecules can be:
Nonpolar
the strongest IMF in nonpolar molecules is dispersion forces
nonpolar organic molecules include hydrocarbons, alkanes, alkenes, alkynes, aromatic hydrocarbons
Polar
strongest force of attraction between molecules is dipole-dipole interactions
organic molecules with oxygen & nitrogen are usually polar molecules
Capable of hydrogen bonding
include alcohols, amines, carboxylic acids, amides
strongest attractive force in all of functional groups
Order of boiling points (1 is highest BP and 4 is lowest BP):
carboxylic acids & amides
alcohols
aldehydes & ketones
hydrocarbons & ethers
Order of water solubility (1 is highest and 5 is lowest):
carboxylic acids & amides
alcohols
aldehydes & ketones
ethers (this is because ethers can accept hydrogen bonding while hydrocarbons can’t)
hydrocarbons
The strength of intermolecular forces in molecules with functional groups depends on:
polarity
capability of hydrogen bonding
Organic molecules can be:
Nonpolar
the strongest IMF in nonpolar molecules is dispersion forces
nonpolar organic molecules include hydrocarbons, alkanes, alkenes, alkynes, aromatic hydrocarbons
Polar
strongest force of attraction between molecules is dipole-dipole interactions
organic molecules with oxygen & nitrogen are usually polar molecules
Capable of hydrogen bonding
include alcohols, amines, carboxylic acids, amides
strongest attractive force in all of functional groups
Order of boiling points (1 is highest BP and 4 is lowest BP):
carboxylic acids & amides
alcohols
aldehydes & ketones
hydrocarbons & ethers
Order of water solubility (1 is highest and 5 is lowest):
carboxylic acids & amides
alcohols
aldehydes & ketones
ethers (this is because ethers can accept hydrogen bonding while hydrocarbons can’t)
hydrocarbons