Short Answer

Hydrogen bonding is stronger than other intermolecular forces because it involves a hydrogen atom bonded to highly electronegative atoms like nitrogen, oxygen, or fluorine. These atoms pull electrons very strongly, making hydrogen highly positive. This strong charge separation creates a powerful attraction toward the lone pairs of nearby electronegative atoms.

Unlike London dispersion and dipole–dipole forces, hydrogen bonding has greater polarity and stronger electrostatic attraction. This makes hydrogen bonds more stable, longer-lasting, and responsible for many unique properties of substances such as water.

Detailed Explanation :

Why Hydrogen Bonding Is Stronger Than Other Intermolecular Forces

Hydrogen bonding is a special and relatively strong type of intermolecular force that arises when hydrogen is directly bonded to highly electronegative elements such as nitrogen (N), oxygen (O), or fluorine (F). These atoms remove electron density from hydrogen very effectively, giving hydrogen a large partial positive charge (δ+). At the same time, the electronegative atoms possess lone pairs that attract this δ+ hydrogen strongly. This strong attraction creates a hydrogen bond, which is significantly stronger than dipole–dipole interactions and London dispersion forces.

Hydrogen bonding is not as strong as covalent or ionic bonding, but it is the strongest among all common intermolecular forces. It plays a key role in determining physical and biological properties such as boiling point, solubility, DNA structure, and protein folding. The reason for its strength can be understood by examining electronegativity, polarity, molecular orientation, and the nature of hydrogen itself.

1. High Electronegativity Creates Strong Polarity

Hydrogen bonding involves N, O, or F because they are the most electronegative elements.
Their high electronegativity causes:

• A large difference in electron-attracting power
• Strong pulling of electrons away from hydrogen
• A large partial positive charge on hydrogen

This strong polarity results in a powerful electrostatic attraction between molecules.

In dipole–dipole forces, polarity exists, but it is not as dramatic as in molecules capable of hydrogen bonding. Therefore, dipole–dipole attractions are weaker.

2. Hydrogen Has No Inner Electrons

Hydrogen is unique because:

• It has only one electron
• When bonded to N, O, or F, this electron is drawn away

This leaves the hydrogen nucleus (a single proton) almost exposed.
Because this proton is very small and highly positive, it can attract lone pairs with great strength.

No other atom behaves like hydrogen in this way.
This is why hydrogen bonds are much stronger than ordinary dipole–dipole interactions.

3. Strong Electrostatic Attraction from Lone Pairs

Hydrogen bonding requires lone pairs on N, O, or F.
These lone pairs are:

• Highly concentrated regions of negative charge
• Positioned so they can interact strongly with δ+ hydrogen

This strong charge-to-charge attraction increases the bond strength.

London dispersion forces rely only on temporary dipoles, which fluctuate and are weaker.
Hydrogen bonds rely on stable, permanent charge separation, making them stronger.

4. Short Distance Between Molecules

Because hydrogen is extremely small, the molecules can come very close to each other.
Shorter distance = stronger force.

Other dipole–dipole interactions involve larger atoms that cannot approach as closely.

Hydrogen bonding therefore results in:

• Shorter intermolecular distances
• Stronger attractions
• Higher boiling and melting points

This explains why water (with hydrogen bonding) boils at 100°C, while H₂S (without hydrogen bonding) boils at –60°C.

5. Directional Nature Increases Strength

Hydrogen bonds are directional, meaning they form in a specific orientation between a hydrogen atom and a lone pair.
This gives them more stability.

In contrast:

• London forces are random and momentary
• Dipole–dipole interactions are not highly directional

Directionality increases the strength and stability of hydrogen bonds.

6. Multiple Hydrogen Bonds Add Extra Strength

In many molecules, multiple hydrogen bonds can form at the same time.

Examples:

• Water molecules form up to four hydrogen bonds
• DNA base pairs form hydrogen bond networks
• Proteins fold based on hydrogen bonding patterns

Each hydrogen bond adds additional strength, creating a strong network that stabilizes structures.

7. Comparison with Other Intermolecular Forces

Hydrogen bonding vs. London dispersion forces:

• Dispersion forces come from temporary dipoles
• They are very weak individually
• Hydrogen bonds arise from strong, permanent charge separation

Hydrogen bonding vs. dipole–dipole forces:

• Dipole–dipole forces occur between molecules with permanent dipoles
• But these dipoles are weaker and less intense
• Hydrogen bonding is a special, stronger form of dipole–dipole attraction

Thus, hydrogen bonding is clearly stronger than both due to its polarity and structural nature.

Conclusion

Hydrogen bonding is stronger than other intermolecular forces because it involves hydrogen attached to highly electronegative atoms, creating intense polarity and a powerful electrostatic attraction. Hydrogen’s small size, the presence of lone pairs on N, O, or F, and the directional nature of the interaction all contribute to the unusual strength of hydrogen bonds. These strong interactions shape the physical properties of many substances and are essential in biological structures like DNA and proteins.