Unit 9: Stratospheric Ozone

Question 1

Why is stratospheric ozone important for life on Earth?

Answer 1

Certain UV rays are harmful to organisms on Earth, but they are filtered by the ozone layer.

Question 2

How is stratospheric ozone formed? (equation)

Answer 2

1. O2 + UV-C —> O + O
2. O + O2 = O3

Question 3

How is stratospheric ozone broken down?

Answer 3

UV-C + O3 = O2 + O —> O2 + O2

Question 4

What are the causes of ozone depletion?

Answer 4

CFCs, used in refrigeration and other products for many years, support the breakdown of ozone in the stratosphere.

Question 5

CFC ozone breakdown equation

Answer 5

1. O3 + Cl —> ClO + O2
2. ClO + O —> Cl + O2

Question 6

What are the effects of ozone depletion?

Answer 6

UV-B and C radiation can reach earth’s surface, harming biological organisms.

Question 7

What are substitutes for CFCs?

Answer 7

HFCs or HCFCs. Still greenhouse gasses, but because they don’t contain chlorine, they don’t deplete the ozone.

Question 8

What are the effects of UV-B and UV-C?

Answer 8

Tissues damage and mutation of DNA.

Question 9

What is absorbed by the ozone layer?

Answer 9

Some of UV-B and all of UV-C.

Question 10

Does ozone depletion connect to global warming?

Answer 10

No