JEE Main20202 Sep 2020Morning ShiftChemistryEnvironmental ChemistryActual
The statement that is not true about ozone is :
Options
- Ain the stratosphere, CFC s release chlorine free radicals CI which reacts with O 3 to give chlorine
- Bin the atmosphere, it is depleted by CFC s.
- Cin the stratosphere, it forms a protective shield against UV radiation.
- DIt is a toxic gas and its reaction with NO gives NO 2
Correct answer
A. in the stratosphere, CFC s release chlorine free radicals CI which reacts with O 3 to give chlorine
Step-by-step solution
In presence of sunlight CFC’s molecule divides & release chlorine free radical, which react with ozone give chlorine monoxide radical (ClO) and oxygen CF 2 Cl 2 g ⟶ UV C ˙ l g + C ˙ F 2 Cl g Cl * ( g ) + O 3 ( g ) ⟶ ClO * ( g ) + O 2 ( g ) ClO ∙ ( g ) + O ( g ) ⟶ Cl ' ( g ) + O 2 ( g )