Atmospheric redox reactions among pollutants

Steps:

• Recall common atmospheric interactions: SO2 acts as a reducing agent for NO2.
• Examine option B: NO2 gains electrons from SO2, forming NO and SO3.
• Verify against known chemistry: This reaction contributes to acid rain precursors.
• Eliminate others by checking if they align with pollutant behaviors.

Why B is correct:

• The reaction NO2 + SO2 → NO + SO3 exemplifies SO2 reducing NO2, a documented atmospheric process forming photochemical smog components.

Why the others are wrong:

• A: CO oxidation to CO2 requires catalysts or UV light, not spontaneous in air.
• C: CO is a reducing agent, not oxidizing SO2 to SO3.
• D: NO reduction to N2 by CO occurs in catalytic converters, not naturally in the atmosphere.

Final answer: B