Are H or OH omitted in Bond Line View?

May 1, 2015

All H atoms attached to C are omitted in a bond-line view, but OH groups are not.

Bond-line notation is a shorthand way of writing organic structural formulas:

• The carbon atoms and the hydrogen atoms attached to them are not shown.
• The bonds between the carbon atoms are shown as lines.
• The vertices and end of lines represent the carbon atoms.
• Any unfilled valences on carbon are assumed to be filled by hydrogen atoms.
• All atoms other than carbon, plus any hydrogen atoms attached to them, are shown.
• Exception: The H in an aldehyde group is usually shown.

For example, the bond line notation for glucose is

In the above diagram, the vertices represent the carbon atoms.

The ends of the lines are not C atoms, because the H and OH groups are shown explicitly.

The H atoms on O must be shown, because they are not on C atoms.

C atoms 2, 3, 4, and 5 have only three bonds, so they each have an H atom as the fourth bond.

C-6 has only two bonds, so it also has two unseen H atoms.