The number of optical isomers of `CH_3CH`(OH)CH(OH)CHO is :-

Options

A. `3`
B. `4`
C. `5`
D. `6`

Answer

To determine the number of optical isomers for the compound \( CH_3CH(OH)CH(OH)CHO \), we will follow these steps:

### Step 1: Identify the Structure
First, we need to draw the structure of the compound \( CH_3CH(OH)CH(OH)CHO \). The compound has the following structure:

```
CHO
|
CH
|
CH(OH)
|
CH3
```

### Step 2: Identify Chiral Centers
Next, we need to identify the chiral centers in the molecule. A chiral center is a carbon atom that is attached to four different groups.

In the structure:
- The first chiral center is at the carbon atom attached to \( CH_3 \), \( OH \), and the next carbon.
- The second chiral center is at the carbon atom attached to \( OH \), \( CH \), and the aldehyde group \( CHO \).

Both of these carbon atoms are chiral centers because they are bonded to four different groups.

### Step 3: Count the Chiral Centers
We have identified that there are 2 chiral centers in the molecule.

### Step 4: Calculate the Number of Optical Isomers
The formula to calculate the number of optical isomers is given by \( 2^n \), where \( n \) is the number of chiral centers.

Here, \( n = 2 \):
\[ \text{Number of optical isomers} = 2^2 = 4 \]

### Conclusion
Thus, the number of optical isomers of \( CH_3CH(OH)CH(OH)CHO \) is 4.

### Final Answer
The number of optical isomers of \( CH_3CH(OH)CH(OH)CHO \) is **4**.

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