Question

An alkene X on ozonolysis gives a mixture of Propan-2-one and methanal. What is X?

• A. Propene
• B. 2-Methylpropene
• C. 2-Methylbut-1-ene
• D. 2-Methylbut-2-ene

Hint:

Ozonolysis breaks double bonds into carbonyl compounds—trace back the products to determine the alkene.

Answer 1

The Correct Option is B

Step 1: Understanding Ozonolysis 
- Ozonolysis of an alkene breaks the double bond and forms aldehydes and ketones. 
- Identifying the correct alkene requires reversing this process. 
Step 2: Identifying the Structure of X 
The products given are Propan-2-one (\( CH_3COCH_3 \)) and methanal (\( HCHO \)).
The only alkene that produces these fragments is 2-Methylpropene (\( CH_3 - C(CH_3) = CH_2 \)).
Final Answer: The correct alkene is 2-Methylpropene. 
 

Answer 2

The alkene X is 2-Methylpropene.

Ozonolysis is a reaction where an alkene is cleaved at the double bond by ozone, producing carbonyl compounds such as aldehydes or ketones depending on the substituents attached to the double bond.

In this case, ozonolysis of alkene X gives a mixture of propan-2-one (acetone) and methanal (formaldehyde). This indicates that the original alkene has a double bond arranged such that one side produces propan-2-one and the other side produces methanal upon cleavage.

2-Methylpropene (also known as isobutylene) has the structure CH₂=C(CH₃)₂. When it undergoes ozonolysis, the double bond between the CH₂ and the substituted carbon breaks, producing methanal (from the CH₂ side) and propan-2-one (from the (CH₃)₂C side).

Therefore, the alkene X that satisfies this condition is 2-Methylpropene.