Question

Which of the following is associated with Ozone destruction in the Stratosphere?
(A) CFCs
(B) Polar stratospheric clouds
(C) UV-B
(D) UV-A
(E) Cl radicals
Correct Answer: Option (4) (A), (B), (C) and (D)

• A. (A) and (E) only
• B. (A), (B), and (E) only
• C. (A), (C), and (D) only
• D. (A), (B), (C), and (E) only

Answer 1

The Correct Option is B

The problem asks for the factors associated with ozone destruction in the stratosphere. To understand this, we need to analyze the effect of each of the provided options presented. 

Factors affecting Ozone Destruction:

1. (A) CFCs: Chlorofluorocarbons (CFCs) are compounds that release chlorine radicals upon exposure to UV radiation. These chlorine radicals are highly effective at destroying ozone molecules. Hence, CFCs are directly associated with ozone depletion.
2. (B) Polar Stratospheric Clouds (PSCs): These clouds provide a surface for chemical reactions that release active chlorine compounds from CFCs, which in turn causes ozone destruction. Therefore, PSCs are indirectly associated with ozone depletion.
3. (C) UV-B: This type of ultraviolet radiation can break down ozone molecules; however, its role is more about being a consequence of ozone layer depletion, as more UV-B reaches the Earth when the ozone layer is thinner.
4. (D) UV-A: It is less energetic compared to UV-B and does not significantly interact with ozone molecules or contribute to their destruction.
5. (E) Cl radicals: Chlorine radicals are released from CFCs and are highly effective in catalyzing the breakdown of ozone molecules, clearly associating Cl radicals with ozone depletion.

Given the explanations above, we can conclude:

• (A) CFCs are associated with ozone destruction.
• (B) Polar Stratospheric Clouds help in the reactions leading to ozone depletion.
• (E) Cl radicals directly contribute to the destruction of ozone molecules.

Thus, the correct answer identifying the factors associated with ozone destruction, according to the options given, is: (A), (B), and (E) only.

Answer 2

The factors associated with ozone destruction in the stratosphere are (A) CFCs, (B) Polar stratospheric clouds, and (E) Cl radicals.

Additional Context:

• Ozone Depletion Process:
  • CFCs (A): Break down to release chlorine atoms
  • Polar stratospheric clouds (B): Provide surface for chlorine activation
  • Cl radicals (E): Catalyze ozone destruction (1 Cl atom can destroy 100,000 ozone molecules)
• About UV Radiation:
  • UV-C (not listed) creates ozone, doesn't destroy it
  • UV-B/A (C/D) are blocked by ozone, not causes of depletion
• Scientific Evidence:
  • Antarctic ozone hole discovered in 1985
  • Montreal Protocol (1987) successfully phased out CFCs

Correct Answer: (2) (A), (B) and (E) only.