Concept:Ozonolysis cleaves the \( \text{C}=\text{C} \) double bond. A double bond attached to two methyl groups on one carbon yields a ketone (acetone) upon cleavage.
Formula:$$ (\text{CH}_3)_2\text{C}=\text{CH}_2 \xrightarrow{\text{O}_3, \text{Zn/H}_2\text{O}} (\text{CH}_3)_2\text{C}=\text{O} + \text{CH}_2\text{O} $$
Solution:- Iso-butene (2-methylpropene) has the structure \( (\text{CH}_3)_2\text{C}=\text{CH}_2 \).
- When the double bond is cleaved by ozone, the carbon bonded to the two methyl groups oxidizes to become a ketone: Acetone (\( \text{CH}_3-\text{CO}-\text{CH}_3 \)).
- The terminal \( \text{CH}_2 \) group oxidizes to formaldehyde (\( \text{HCHO} \)).
Why other options are incorrect:- 2-butene (\( \text{CH}_3\text{CH}=\text{CHCH}_3 \)) yields two molecules of acetaldehyde.
- 1-butene yields propionaldehyde and formaldehyde.
- 2-butyne would yield carboxylic acids upon oxidative cleavage.
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