Which compounds will show optical isomerism

Options

A. 2 - Butanol
B. 2 -Amino butane
C. Lactic acid
D. All of these

Answer

To determine which compounds will show optical isomerism, we need to identify the presence of chiral carbons in each compound. A chiral carbon is a carbon atom that has four different groups attached to it, leading to non-superimposable mirror images.

### Step-by-Step Solution:

1. **Identify the Compounds**: We will analyze the following compounds:
- 2-butanol
- 2-amino butane
- Lactic acid

2. **Draw the Structures**:
- **2-butanol**: The structure can be represented as:
```
CH3-CH(OH)-CH2-CH3
```
- **2-amino butane**: The structure can be represented as:
```
CH3-CH(NH2)-CH2-CH3
```
- **Lactic acid**: The structure can be represented as:
```
CH3-CH(OH)-COOH
```

3. **Identify Chiral Carbons**:
- **For 2-butanol**: The carbon with the hydroxyl group (OH) is attached to:
- CH3
- OH
- CH2
- H
Since all four groups are different, this carbon is chiral.

- **For 2-amino butane**: The carbon with the amino group (NH2) is attached to:
- CH3
- NH2
- CH2
- H
Again, all four groups are different, making this carbon chiral.

- **For lactic acid**: The carbon with the hydroxyl group (OH) is attached to:
- CH3
- OH
- COOH
- H
This carbon also has four different groups, confirming it is chiral.

4. **Conclusion**: Since all three compounds (2-butanol, 2-amino butane, and lactic acid) contain chiral carbons, they will all show optical isomerism.

### Final Answer:
All three compounds show optical isomerism.