Polychlorinated biphenyls (PCBs)have been banned because they are an environmental hazard.Which of the following was NOT a reason for banning them?
A)PCBs degrade slowly in nature.
B)PCBs are nonpolar compounds and do not dissolve readily in water.
C)PCBs have high electrical resistance and are excellent insulating materials.
D)They lower the glass transition temperature, Tg, when they are added to a polymer.

Question

Quizplus · Accepted Answer

PCBs being excellent insulating materials was not a reason for their ban. The other options all contribute to the environmental hazard posed by PCBs. PCBs degrade slowly in nature and accumulate in the food chain, leading to toxic effects in animals and humans. They are nonpolar compounds and do not dissolve readily in water, which makes them persistent in the environment. Adding PCBs to polymers lowers the glass transition temperature, which can lead to structural failure and increase the likelihood of leaks and spills.

Polychlorinated Biphenyls (PCBs)have Been Banned Because They Are an Environmental