Q2 (NDA-II/2016) Environment & Ecology › Pollution & Conservation › Ozone layer protection Answer Verified

Statement 1 : Ozone is a tn-atomic molecule of oxygen. Statement II ; Ozone is concentrated mainly in stratosphere.

Both die statements are individually true and Statement II is the correct explanation of Statement I

Both the statements are individually true but Statement II is not the correct explanation of Statement I

Statement I is true but Statement II is false

Statement I is false but Statement II is true

Result

Your answer: — · Correct: B

Explanation

Statement I is true as ozone (O3) is a triatomic molecule consisting of three oxygen atoms [5]. It is an allotrope of oxygen formed when an oxygen molecule (O2) reacts with a single oxygen atom [4]. Statement II is also true because approximately 90% of atmospheric ozone is concentrated in the stratosphere, specifically in the 'ozone layer' located between 10 and 50 kilometers above the Earth's surface [6]. While both statements are factually correct, Statement II does not explain why ozone is triatomic. The triatomic nature of ozone is a result of chemical bonding and photochemical reactions involving ultraviolet radiation and molecular oxygen [4]. The location of its concentration (stratosphere) is a consequence of where the conditions for its formation and stability are most favorable, rather than a reason for its molecular structure.

Sources

[1] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 20: Earths Atmosphere > Ozone (O3) > p. 272
[2] Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 6: Environmental Degradation and Management > ozone depletion > p. 11
[5] https://www.csl.noaa.gov/assessments/ozone/2010/twentyquestions/Q1.pdf
[3] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 19: Ozone Depletion > OTSNE $$FUETION > p. 267
[4] https://csl.noaa.gov/assessments/ozone/2006/chapters/Q2.pdf
[6] https://en.wikipedia.org/wiki/Ground-level_ozone

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Statement 1 : Ozone is a tn-atomic molecule of oxygen. Statement II ; Ozone is concentrated mainly in stratosphere.

Explanation

SIMILAR QUESTIONS

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Statement I : Chlorine radicals (Cl) initiate the chain reaction for ozone depletion. Statement I : Gaseous hypo- chlorous acid and chlorine are photolysed by sunlight.

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