The total number of structural isomers having the molecular formula `C_(5)H_(12)O` is

Explanation

To determine the total number of structural isomers for the molecular formula \( C_5H_{12}O \), we will analyze the possible structures based on the functional groups that can be formed. The primary functional groups we will consider are alcohols and ethers.

### Step-by-Step Solution:

1. **Identify Possible Functional Groups**:
- The molecular formula \( C_5H_{12}O \) can represent alcohols and ethers.
- Alcohols have the functional group -OH, while ethers have the structure R-O-R'.

2. **Count Structural Isomers for Alcohols**:
- **1-Pentanol**: \( CH_3(CH_2)_4OH \)
- **2-Pentanol**: \( CH_3CH_2CH(OH)CH_2CH_3 \)
- **3-Pentanol**: \( CH_3CH_2CH_2CH(OH)CH_3 \)
- **2-Methyl-1-butanol**: \( CH_3CH(CH_3)CH_2CH_2OH \)
- **2-Methyl-2-butanol**: \( CH_3C(OH)(CH_3)CH_2CH_3 \)
- **3-Methyl-1-butanol**: \( CH_3CH_2CH(CH_3)CH_2OH \)
- **3-Methyl-2-butanol**: \( CH_3CH(CH_3)CH(OH)CH_3 \)
- **2,2-Dimethyl-1-propanol**: \( (CH_3)_2C(OH)CH_2CH_3 \)

Total alcohol isomers = 8.

3. **Count Structural Isomers for Ethers**:
- **Methyl butyl ether**: \( CH_3CH_2CH_2CH_2OCH_3 \)
- **Ethyl propyl ether**: \( CH_3CH_2OCH_2CH(CH_3)CH_3 \)
- **Isobutyl methyl ether**: \( CH_3CH(CH_3)CH_2OCH_3 \)
- **Ethyl isopropyl ether**: \( CH_3CH_2O(CH_3)CH(CH_3)CH_3 \)
- **Dimethyl ether**: \( CH_3OCH_3 \)

Total ether isomers = 5.

4. **Calculate Total Structural Isomers**:
- Total structural isomers = Total alcohol isomers + Total ether isomers
- Total structural isomers = 8 (alcohols) + 5 (ethers) = 13.

### Final Answer:
The total number of structural isomers having the molecular formula \( C_5H_{12}O \) is **13**.