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Name: Arlene Langley
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Why do fluorocarbons destroy the ozone?

Okay, here is the scoop: Normally, ozone (O3) goes through a natural cycle in the atmosphere which goes something like this --

oxygen (O2) ==> hit by UV light ==> O. + O. (O. + O2) ==> O3
O3 == > hit by UV light ==> O. + O2
O. + O. ==> O2 (small amounts..)

When halofluorocarbons are introduced into the atmosphere, they do much the same thing:

Cl-(FC) ==> hit by UV light ==> Cl + (FC).
Then Cl. + O3 ==> ClO- + O2
ClO- + O3 ==> Cl. + 2 O2

In other words, the atmosphere has a certain amount of O3 ozone because of its exposure to UV radiation from the sun. O3 is a fairly unstable compound, and does not take a lot of a kick to break apart, but still does not have enough energy to break itself apart. It usually takes UV energy to break it, but when a halofluorocarbon is split by UV radiation, the chlorine radical released can give the ozone the energy it needs to break up. But notice: Where does the chlorine radical go after this? It goes back and does it all over again -- on the average of around 100,000 times. Scary, huh?


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