What is a result of adding hydrogen to CFCs?

What is a result of adding hydrogen to CFCs?

• A. It allows oxidation and makes HCFCs reactive
• B. It prevents breakdown in the atmosphere
• C. It increases chlorine release
• D. It reduces ozone depletion potential

Answer: (A)

Substituting hydrogen for chlorine in CFCs forms HCFCs, and this changes how the molecule behaves in the atmosphere. The hydrogen atoms make the HCFCs more susceptible to attack by atmospheric oxidants, so they oxidize more readily and break down in the troposphere. This increased oxidation and reactivity is the direct result of adding hydrogen. As a consequence of breaking down earlier, less chlorine reaches the stratosphere, which lowers ozone depletion potential, but the primary observable effect described here is the enhanced oxidation of HCFCs. The other options describe outcomes that don’t fit the immediate atmospheric chemistry: they don’t prevent breakdown, they don’t increase chlorine release to the stratosphere, and while ozone depletion potential is reduced, that is a downstream effect.

Substituting hydrogen for chlorine in CFCs forms HCFCs, and this changes how the molecule behaves in the atmosphere. The hydrogen atoms make the HCFCs more susceptible to attack by atmospheric oxidants, so they oxidize more readily and break down in the troposphere. This increased oxidation and reactivity is the direct result of adding hydrogen. As a consequence of breaking down earlier, less chlorine reaches the stratosphere, which lowers ozone depletion potential, but the primary observable effect described here is the enhanced oxidation of HCFCs. The other options describe outcomes that don’t fit the immediate atmospheric chemistry: they don’t prevent breakdown, they don’t increase chlorine release to the stratosphere, and while ozone depletion potential is reduced, that is a downstream effect.