Polychlorinated biphenyls (PCBS) are a major environmen- tal problem. These oily substances have many uses, but they resist breakdown by bacterial action when spilled in the environment and, being fat-soluble, can accumulate to dangerous concentrations in the fatty tissues of fish and animals. One little-appreciated complication in controlling the problem is that there are 209 different PCBS, all now in the environment. They are generally similar, but their solu- bilities in fats differ considerably. The best measure of this is Kow, the equilibrium constant for the partition of a PCB between the fat-like solvent octanol and water. PCB(aq) = 2 PCB(octanol) An equimolar mixture of PCB-2 and PCB-11 in water is treated with an equal volume of octanol. Determine the ratio between the amounts of PCB-2 and PCB-11 in the water at equilibrium. At room temperature, Kow is 3.98 × 104 for PCB-2 and 1.26 × 10° for PCB-11.

Polychlorinated biphenyls (PCBS) are a major environmen- tal problem. These oily substances have many uses, but they resist breakdown by bacterial action when spilled in the environment and, being fat-soluble, can accumulate to dangerous concentrations in the fatty tissues of fish and animals. One little-appreciated complication in controlling the problem is that there are 209 different PCBS, all now in the environment. They are generally similar, but their solu- bilities in fats differ considerably. The best measure of this is Kow, the equilibrium constant for the partition of a PCB between the fat-like solvent octanol and water. PCB(aq) = 2 PCB(octanol) An equimolar mixture of PCB-2 and PCB-11 in water is treated with an equal volume of octanol. Determine the ratio between the amounts of PCB-2 and PCB-11 in the water at equilibrium. At room temperature, Kow is 3.98 × 104 for PCB-2 and 1.26 × 10° for PCB-11.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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