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Flashcards in Organohalogens Deck (5)
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1

Uses of organohalogen compounds

Molecules that contain at least 1 halogen joined to carbon chain
Pesticides
Not found in environment, not broken down by environment

2

Ozone layer

Outer edge of stratosphere
Absorb most of UVB radiation
Depletion allows more to reach earth

Oxygen broken down into oxygen radicals and reformed by UV to form ozone at same rate

CFCs upset equilibrium

3

CFCs and the ozone

CFCs are very stable, strong bonds
Less stable in stratosphere, broken down by UV, homolytic fission, radicals formed
CCl bond broken, lowest enthalpy

4

Photodissociation

CF2Cl2 => CF2Cl +Cl *
Cl* + O3 => ClO* + O2
ClO* + O => Cl* + O2
O3 + O => 2O2

5

Are CFCs responsible for all ozone depleting reactions

Nitrogen radicals are just as bad

NO* + O3 => NO2* + O2
NO2 + O => NO* + O2