sustainability of ozone layer

Question 1

what is a CFC?

Answer 1

CFC’s are manmade molecules of carbon, chlorine and fluorine only

Question 2

what is the problem with CFC’s?

Answer 2

they are too unreactive, they can survive long enough in the atmosphere to reach the stratosphere where the intense high energy UV rays cause photodissociation and break the bond via homolytic fission producing radicals

Question 3

what do CL radicals act as?

Answer 3

a catalyst for the breakdown of the ozone

Question 4

what is being done about the ozone depletion?

Answer 4

because of the concern about increase in skin cancer, affect on eyes, immune system, crops, weather ect. a global treaty was signed phasing out the use of CFC’s

Question 5

what has been used in the short term to replace CFC’s?

Answer 5

HCFC’s, hydrochlorofluorocarbons, which contain at least one C-H bond meaning they are less stable and majority react in the troposphere

Question 6

why is it better to use HCF’s instead of HCFC’s in the long term?

Answer 6

HCF’s still contain at least one C-H meaning they are less stable than CFC’s and mainly react in the troposphere, those that don’t react in the troposphere do not contain chlorine so cannot contribute to the breakdown of the ozone

Question 7

what other environmental problem do HCF’s and HCFC’s have?

Answer 7

they are both powerful greenhouse gases which contribute to global warming. despite HFC’s not depleting the ozone they are still being phased out.