Number of optical isomers of lactic acid are

Options

A. `1`
B. `2`
C. `3`
D. `4`

Explanation

To determine the number of optical isomers of lactic acid, we can follow these steps:

### Step 1: Identify the Structure of Lactic Acid
Lactic acid (C₃H₆O₃) has the following structure:

```
CH3
|
C(OH)
|
COOH
```

### Step 2: Identify Chiral Centers
A chiral center is a carbon atom that is attached to four different groups. In lactic acid, the carbon atom that has the hydroxyl group (–OH), the carboxyl group (–COOH), a hydrogen atom (–H), and a methyl group (–CH₃) is a chiral center.

### Step 3: Count the Number of Chiral Centers
Lactic acid has **one chiral center**.

### 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.

Since lactic acid has one chiral center:
\[ n = 1 \]
\[ \text{Number of optical isomers} = 2^1 = 2 \]

### Conclusion
Thus, lactic acid has **two optical isomers**.

### Final Answer
The number of optical isomers of lactic acid is **2**.

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