Which chemical compound has been banned in most countries due to its link to stratospheric ozone depletion?

• A. CFC-12 (dichlorodifluoromethane)
• B. CO2 (carbon dioxide)
• C. SO2 (sulfur dioxide)
• D. NH3 (ammonia)

Answer: (A)

Verified step by step guidance

1. Understand the context of the problem: it asks which chemical compound has been banned in most countries due to its link to stratospheric ozone depletion.
2. Recall that stratospheric ozone depletion is primarily caused by compounds that release chlorine or bromine atoms in the upper atmosphere, which catalyze the breakdown of ozone (O3).
3. Identify the compounds listed: CFC-12 (dichlorodifluoromethane), CO2 (carbon dioxide), SO2 (sulfur dioxide), and NH3 (ammonia).
4. Recognize that CFC-12 is a chlorofluorocarbon, known for releasing chlorine atoms that destroy ozone, leading to its regulation and ban under international agreements like the Montreal Protocol.
5. Understand that CO2, SO2, and NH3 do not have the same direct effect on ozone depletion; CO2 is a greenhouse gas, SO2 contributes to acid rain, and NH3 is a common base and fertilizer component.