Definition: Hydrogen bonding is a strong type of intermolecular force that occurs when a
hydrogen atom, covalently bonded to a highly electronegative atom (N, O, or F), is attracted to a
lone pair of electrons on a neighboring electronegative atom (N, O, or F).
Diagram 1: Bond Dipole within a Single Molecule (Water)
In a water molecule (𝐻2 𝑂), Oxygen is more electronegative than Hydrogen. This creates a polar
covalent bond where the electrons spend more time near the Oxygen.



Oxygen atom: carries a partial negative charge (𝛿 − ).
Hydrogen atoms: carry a partial positive charge (𝛿 + ).
Bond Dipole: Represented by an arrow with a cross at the tail, pointing from the positive
Hydrogen toward the negative Oxygen.
Visual Representation:
(δ-)
O
/ \
+-->
<--+
H
H
(δ+)
(δ+)
(Dipole arrows pointing to O)
Diagram 2: Hydrogen Bonding Between Multiple Molecules
The hydrogen bond is the electrostatic attraction between the molecules (shown as dotted lines),
not the solid lines inside the molecule.
Visual Representation:
Molecule 1
(δ-)
O
/ \
(δ+)H (δ+)H
Molecule 2
(δ-)
O
/ \
. . . . (δ+)H (δ+)H
^
|
Hydrogen Bond
(Attraction between
δ+ H and δ- O)
Key features to include in your sketch:
1. Intramolecular bonds: Solid lines between O and H.
2. Intermolecular Hydrogen bonds: Dotted or dashed lines between the H of one
molecule and the O of another.
3. Partial Charges: Labels for 𝛿 + on all H atoms and 𝛿 − on all O atoms.