Q D D T is a toxin still found in the fatty tissues of some...

Q $\triangle D D T$ is a toxin still found in the fatty tissues of some animals. DDT was transported into our lakes and streams as runoff from agricultural operations where it was originally used several years ago as an insecticide. In the lakes and streams it did not dissolve to any great extent; it collected in the lake and stream bottoms. It entered the bodies of animals via fatty tissues in their diet; microorganisms collected the DDT, the fish ate the microorganisms, and so on. Fortunately, much of the once large quantities of DDT in lakes and streams has biodegraded. Based on this information, what can you conclude regarding the intermolecular forces present in DDT?

Labs

Want to see this concept in action?

NEW

Explore this concept interactively to see how it behaves as you change inputs.

View Labs

Key Concepts

Molecular Polarity

Molecular polarity refers to the distribution of electrical charge within a molecule. In the context of DDT, the fact that it accumulates in fatty tissues and does not dissolve well in water indicates that it is nonpolar. Nonpolar molecules have an even distribution of electrons, making them hydrophobic, which is why they tend to dissolve in lipids rather than water.

London Dispersion Forces

London dispersion forces are the weakest type of intermolecular force and arise from temporary fluctuations in electron density in nonpolar molecules. In the case of DDT, its nonpolar nature means it primarily relies on London dispersion forces to hold its molecules together. These forces are sufficient for interactions between nonpolar compounds, contributing to DDT's persistence in the environment.

Hydrophobic Interactions

Hydrophobic interactions describe the tendency of nonpolar substances to aggregate in an aqueous environment to minimize their exposure to water. The bioaccumulation of DDT in fatty tissues is a manifestation of its hydrophobic character, which is directly linked to its nonpolarity and the corresponding intermolecular forces that are predominantly London dispersion forces.

Please give Ace some feedback