GRADED A+
alcohol (carbon-oxygen)
aldehyde (carbon-oxygen)
ketone (carbon-oxygen)
carboxylic acid (carbon-oxygen)
,ether (carbon-oxygen)
acid anhydride (carbon-oxygen)
sulfhydryl group (carbon-sulfur)
disulfide (carbon-sulfur)
,amino group (carbon-nitrogen)
Quaternary Amine (carbon-nitrogen)
Phosphoester
Ester
, Thioester
Amide
aliphatic
molecule without benzene ring
aromatic
molecule with benzene ring
Proline