Molecular formulae of an optically active organic compound is
`C_(4) H_(10) O` . Its structure is

Options

A. `C_(2) H_(5) OC_(2) H_(5)`
B. `CH_(3) OC_(3) H_(7)`
C. `CH_(3) CH_(2) CH_(2) CH_(2) OH`
D. `CH_(3) CHOHCH_(2) CH_(3)`

Answer

To determine the structure of an optically active organic compound with the molecular formula C4H10O, we need to identify a structure that contains a chiral center. A chiral center is typically a carbon atom bonded to four different groups.

### Step-by-Step Solution:

1. **Identify the Molecular Formula**: The given molecular formula is C4H10O. This indicates that the compound contains 4 carbon atoms, 10 hydrogen atoms, and 1 oxygen atom.

2. **Understand Optical Activity**: A compound is optically active if it has at least one chiral center. A chiral center is a carbon atom that is bonded to four different substituents.

3. **Explore Possible Structures**: We need to explore different structural isomers of C4H10O to find one with a chiral center. The common structural forms for this molecular formula include:
- Butanol (1-butanol, 2-butanol, etc.)
- Ether structures (like diethyl ether)
- Other possible arrangements.

4. **Examine Each Structure for Chirality**:
- **1-Butanol**: CH3-CH2-CH2-CH2OH (not chiral)
- **2-Butanol**: CH3-CH(OH)-CH2-CH3 (this has a chiral center)
- **Diethyl ether**: CH3-CH2-O-CH2-CH3 (not chiral)
- **Isobutyl alcohol**: CH3-CH(CH3)-CH2OH (not chiral)
- **Butyl methyl ether**: CH3-CH2-CH2-O-CH3 (not chiral)

5. **Identify the Chiral Center**: In the case of 2-butanol (CH3-CH(OH)-CH2-CH3), the carbon atom bonded to the hydroxyl group (OH) is attached to four different groups:
- Methyl group (CH3)
- Hydroxyl group (OH)
- Ethyl group (CH2-CH3)
- Hydrogen atom (H)

6. **Conclusion**: Since 2-butanol has a chiral center, it is optically active. Therefore, the structure of the optically active organic compound with the molecular formula C4H10O is 2-butanol.

### Final Structure:
The structure of the optically active compound is:
```
CH3
|
CH3-CH-CH2-CH3
|
OH
```