Alkenes on treating with `O_3` and then the product on reduction may give

Options

A. `CO_2` and water
B. aldehydes
C. ketones
D. none of the above

Answer

To solve the question regarding the products formed when alkenes are treated with ozone (O₃) and then reduced, we can follow these steps:

### Step 1: Understand Ozonolysis
Ozonolysis is a reaction where alkenes react with ozone to form ozonides. This reaction typically cleaves the double bond of the alkene.

### Step 2: Identify the Structure of the Alkene
Let's consider a simple terminal alkene, such as propene (CH₃-CH=CH₂). The double bond is between the second and third carbon atoms.

### Step 3: Formation of Ozonide
When propene undergoes ozonolysis, ozone adds across the double bond to form a molozonoid (ozonide). The structure of the ozonide can be represented as follows:

```
O
/ \
CH₃-C C-CH₂
\ /
O
```

### Step 4: Cleavage of Ozonide
The ozonide is then cleaved to form carbonyl compounds. The cleavage occurs at the carbon-carbon double bond, resulting in two carbonyl groups.

### Step 5: Hydrolysis and Reduction
Upon hydrolysis (often using a reducing agent like zinc in water), the ozonide breaks down to yield aldehydes and/or ketones. For propene, the products will be:

- Acetone (CH₃COCH₃) - a ketone
- Formaldehyde (HCHO) - an aldehyde

### Step 6: Conclusion
Thus, the products of ozonolysis followed by reduction of a terminal alkene are both aldehydes and ketones.

### Final Answer
The products obtained from the ozonolysis of alkenes followed by reduction are aldehydes and ketones.

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