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Atmospheric Pollution — CHEMISTRY STD 9 — Question

ICSE BoardEnglish MediumSTD 9CHEMISTRYAtmospheric Pollution3 Marks
Question
Explain the formation of ozone in the atmosphere.
✓

Answer

In the atmosphere, ozone is formed by the action of ultraviolet rays of the Sun on oxygen.
$3O_{2(g)}→ 2O_3(g)$
High-energy UV radiation breaks oxygen molecules into oxygen atoms.
$O_2 + Far UV → O + O$
Oxygen atom reacts with the oxygen molecules to form ozone.
$O + O_2→ O_3$​​​​​​​
Net reaction is
$2O_2 +$ Far $UV → 2O_3​​​​​​​$​​​​​​​

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