29. CFCs are a problem because they
a. have been released in large quantities in the past
b. break down to reactive free chlorine atoms
c. attack ozone molecules in the upper atmosphere
d. all of the above
D?
10. Ozone depletion in the atmosphere
a. leads to the formation of acid precipitation
b. leads to a rise in chlorofluorocarbons
c. allows more harmful radiation from the sun to reach the earth
d. both b and c
D?
Thanks
-MC
29. OK
10. http://library.thinkquest.org/26026/Environmental_Problems/ozone_depletion_-_effects.html
So 10 is just C?
-MC
Si, C
Gracias!
PS>Why were we blocked yesterday?
Thanks!
-MC
I don't know anything about that.
For question 29, the correct answer is d. "all of the above." CFCs (chlorofluorocarbons) are a problem because they have been released in large quantities in the past, they break down into reactive free chlorine atoms, and these chlorine atoms attack ozone molecules in the upper atmosphere.
To arrive at this answer, you can break down the options and examine each statement individually:
a. CFCs have been released in large quantities in the past: This is true. CFCs were widely used in aerosol sprays, refrigeration, and air conditioning systems before their harmful effects on the ozone layer were recognized.
b. CFCs break down to reactive free chlorine atoms: This is also true. When CFCs are released into the atmosphere, they are broken down by solar ultraviolet radiation. This breakdown releases chlorine atoms that are highly reactive.
c. These chlorine atoms attack ozone molecules in the upper atmosphere: This is also true. The reactive chlorine atoms can catalytically destroy ozone molecules, leading to the depletion of the ozone layer.
Since all three statements are true, the correct answer is d. "all of the above."
For question 10, the correct answer is also d. "both b and c." Ozone depletion in the atmosphere leads to a rise in chlorofluorocarbons (CFCs) and allows more harmful radiation from the sun to reach the Earth.
To arrive at this answer, let's examine each option:
a. Ozone depletion leads to the formation of acid precipitation: This statement is incorrect. Ozone depletion is not directly linked to the formation of acid precipitation.
b. Ozone depletion leads to a rise in chlorofluorocarbons (CFCs): This statement is true. When the ozone layer is depleted, more UV radiation reaches the Earth's surface, which can break down other compounds and release reactive chlorine and bromine atoms. These atoms can then catalytically destroy ozone molecules and deplete the ozone layer.
c. Ozone depletion allows more harmful radiation from the sun to reach the Earth: This statement is also true. The ozone layer acts as a shield, absorbing most of the sun's harmful UV radiation. When the ozone layer is depleted, more UV radiation can reach the Earth's surface, which has various harmful effects on both human health and ecosystems.
Since both statements b and c are true, the correct answer is d. "both b and c."
I hope this helps! Let me know if you have any further questions.