Molecular weight (g/mol)
Number of Nitrogen atoms
Number of Halogen (Fluorine, Chlorine, Bromine) atoms
Bridged rings should be counted as +1 for every bridge. Linked rings count each ring. For example, naphthalene and camphor both count as 2 rings.
Number of rings in the molecule, both aromatic and aliphatic
Number of tertiary or quarternary Carbon atoms
Number of heteroatoms within rings
Number of unique substituents on aromatic ring systems in the molecule
For example, Toluidine counts as 2. Trichlorobenzene counts as 1. Note that ring systems can also be substituents to other ring systems, e.g. 1-chlorobiphenyl computes to 3.
Number of total functional groups
Number of Oxygen atoms in carbonyl groups
(i.e. aldehydes or ketones)
Number of Oxygen atoms except those in carbonyl groups