Which intermolecular forces are present in Hypochlorous acid (HClO) and in sodium hydroxide?
The Correct Answer and Explanation is:
Correct Answer:
- Hypochlorous acid (HClO) exhibits hydrogen bonding, dipole-dipole interactions, and London dispersion forces.
- Sodium hydroxide (NaOH) exhibits ionic bonding (in solid form) and ion-dipole interactions (in aqueous solution), along with London dispersion forces.
Explanation:
Intermolecular forces are interactions between molecules that affect physical properties such as boiling point, solubility, and state of matter. The nature of these forces depends on the structure and polarity of the substances involved.
Hypochlorous acid (HClO) is a molecular compound composed of hydrogen (H), chlorine (Cl), and oxygen (O). The molecule is polar due to the electronegativity differences between its atoms and its bent molecular shape. As a result, dipole-dipole interactions are present. Additionally, because the hydrogen atom is bonded to a highly electronegative oxygen atom, hydrogen bonding occurs between HClO molecules—an especially strong type of dipole-dipole force. Finally, London dispersion forces (temporary induced dipoles) are always present in all molecules, though they are generally weak in small polar molecules like HClO.
Sodium hydroxide (NaOH) is an ionic compound composed of Na⁺ and OH⁻ ions in the solid state. In solid form, ionic bonding—the electrostatic attraction between oppositely charged ions—is the dominant force. However, when NaOH dissolves in water, the ions dissociate and interact with water molecules. This introduces ion-dipole interactions, a strong intermolecular force between the dissolved ions (Na⁺ and OH⁻) and the polar water molecules. These ion-dipole forces are responsible for the high solubility of NaOH in water and play a crucial role in its behavior in solution. London dispersion forces are also present but are negligible compared to the strong ionic and ion-dipole interactions.
In summary, HClO involves hydrogen bonding, dipole-dipole forces, and dispersion forces, while NaOH involves ionic bonding in solid form and ion-dipole interactions in solution, with minor dispersion forces present in both. Understanding these forces helps explain each compound’s physical and chemical properties.
