Which of the following is NOT required for the production of bad ozone?

Question

BlackTom AI · Accepted Answer

Ground-level (bad) ozone forms through photochemical reactions involving nitrogen oxides (NOx), volatile organic compounds (VOCs), and sunlight — not directly from carbon dioxide.

1) Relevant knowledge points and concepts
- "Bad" ozone = tropospheric (ground-level) ozone, a secondary pollutant harmful to health and vegetation.
- Key precursors: NOx (NO and NO2) and VOCs. Sunlight (UV/visible) provides the energy to drive photochemical reactions.
- Carbon dioxide (CO2) is a very stable, fully oxidized carbon species and does not enter the radical chemistry that produces ozone.

2) Complete reasoning process step by step
- Step A: Sunlight photolyzes NO2:
  NO2 + hv (λ < ~420 nm) → NO + O(3P)
- Step B: Atomic oxygen reacts with molecular oxygen to form ozone:
  O(3P) + O2 + M → O3 + M
  (This pair of reactions cycles NO2 ⇄ NO + O and by itself does not lead to net O3 accumulation because NO will destroy O3: NO + O3 → NO2 + O2.)
- Step C: VOCs (or CO, CH4, etc.) react with OH and form peroxy radicals (RO2, HO2), which oxidize NO to NO2 without consuming ozone:
  RH + OH → R• + H2O → RO2• (sequence)
  RO2• + NO → RO• + NO2
  NO2 formed this way can be photolyzed again to produce additional O3, allowing O3 to accumulate.

3) Intermediate steps shown
- Photolysis: NO2 + hv → NO + O
- Ozone formation: O + O2 + M → O3 + M
- VOC-driven NO → NO2 conversion: RO2 + NO → RO + NO2
- Net effect: VOCs + NOx + sunlight → buildup of O3

4) Why the correct answer is correct
- CO2 does not form the reactive radicals (RO2, HO2) needed to convert NO to NO2 in a way that leads to net ozone formation. CO2 is the oxidation end-product of carbon-containing fuels and is chemically inert in these atmospheric photochemical cycles. Thus CO2 is not required for the production of tropospheric ozone.

5) Why other options (NOx, VOCs, sunlight) are incorrect choices if they were offered
- NOx is required because NO2 photolysis produces O atoms that form O3.
- VOCs (or CO/CH4 as reactive carbon species) are required because their oxidation produces peroxy radicals that turn NO into NO2 without destroying O3, allowing net accumulation.
- Sunlight is required because photolysis of NO2 (the initiating step) requires photons.

6) Conclusion
Carbon dioxide is not required for the production of bad (ground-level) ozone; the correct answer is carbon dioxide. This matches the provided answer.

Which of the following is NOT required for the production of bad ozone?单项选择题

类似问题

Researchers noted that __________ (major cannabis state) is especially vulnerable to the cannabis ozone-creating effects of terpenes due to the unique high-desert environment where few other VOCs are present.***

What are the pollutants that react with the VOCs and the Sun to create ozone?

Due to sunlight being less intense on a cloudy day than a sunny day, ozone levels on a cloudy day are lower than on a sunny day.

Which of the following would most likely reduce the concentration of ground-level ozone in the air of a city?

In metropolitan areas, the concentration of ozone in the atmosphere drops at night because __________.

The implementation and loading phase of the Database Life Cycle (DBLC) involves _____.

Which of the following parameters is used to determine the concentration of protein in a spectrophotometer?

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单