In the following sequence of reactions, the alkene affords the compound 'B'
`CH_3CH - CHCH_3 overset(O_3)(to) A underset(Zn) overset(H_2O)(to)B` the compound B is

Options

A. `CH_3CH_2CHO`
B. `CH_3COCH_3`
C. `CH_3CH_2COCH_3`
D. `CH_3CHO`

Answer

To solve the problem step by step, we will analyze the given alkene and the reactions it undergoes to form compound B.

### Step 1: Identify the Alkene
The alkene provided is `CH3CH=CHCH3`. This can be represented as 2-butene.

### Step 2: Ozonolysis Reaction
When 2-butene undergoes ozonolysis, it reacts with ozone (O3). This reaction cleaves the double bond and forms an ozonide intermediate. The ozonide formed from 2-butene will be:

- The structure of the ozonide (compound A) can be represented as:
```
O
/ \
CH3 CH3
| |
C C
| |
H H
```

### Step 3: Reduction of Ozonide
Next, the ozonide (compound A) is treated with zinc (Zn) in the presence of water (H2O). This step is known as reductive workup. During this reaction, the ozonide is cleaved to form carbonyl compounds (aldehydes or ketones) which then can be further reduced to alcohols.

### Step 4: Identify the Products
The ozonide from 2-butene will yield two molecules of acetaldehyde (CH3CHO) when cleaved. However, in the presence of zinc and water, these aldehydes can be reduced to ethanol (C2H5OH).

### Step 5: Final Product
Thus, the final compound B formed from the reaction sequence is ethanol (C2H5OH).

### Conclusion
The compound B is ethanol (C2H5OH).

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