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RRB Junior Engineer / DMS / CMA 2019 · Question 15 of 3719

Which of the following pollutants is the major contributor to photochemical smog?

Chemistry - Chemical Reactions

  1. Aa. Hydroperoxides
  2. Bb. OzoneCorrect
  3. Cc. Nitrogen dioxide
  4. Dd. Peroxynitrates

Answer: B. b. Ozone

Explanation

Ozone: • Ozone is an allotrope of Oxygen, with molecular formula 03. • It is stabilised by resonance i.e. delocalisation of electrons. • It is a pale blue coloured gas present in our the stratosphere layer. • It protects us from the harmful Ultraviolet Rays coming from the sun. • The chlorofluorocarbons (CFCs) are the ozone-depleting agents originating from Air Conditioners, Refrigerators and Aerosols. • Montreal Protocol was signed on September 16, 1987, for the protection of Ozone, that entered into force on January 1, 1989. • But when Ozone is present at ground level, instead of atmosphere it acts as a pollutant.

Source: RRB JE 2019 CBT-1 (24-May-2019 Shift-2) — ixambee compilation with answer key and solutions · reliable-secondary

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