Debye

Definition

The Debye is a unit of electric dipole moment, used to measure the separation of positive and negative charges in a system. It is commonly employed in chemistry to describe the polarity of molecules.

5 Must Know Facts For Your Next Test

1. The Debye is named after the physicist Peter J. W. Debye.
2. One Debye (D) equals $3.33564 \times 10^{-30}$ coulomb-meters.
3. Molecular polarity, which affects colligative properties such as boiling point elevation and freezing point depression, can be quantified using the Debye.
4. Water has a dipole moment of approximately 1.85 Debye, indicating its high polarity.
5. Debye units are essential for understanding interactions in solutions, such as hydrogen bonding and Van der Waals forces.

Review Questions

• What does one Debye measure in terms of molecular properties?
• How does molecular polarity, measured in Debyes, affect boiling point elevation?
• Why is water's dipole moment significant when discussing colligative properties?

Related terms

Dipole Moment: A measure of the separation of positive and negative charges within a molecule.

Polarity: The distribution of electrical charge over atoms joined by a bond; determines how molecules interact with each other.

Van der Waals Forces: Weak attractive forces between molecules due to temporary dipoles induced in atoms or molecules.