Find the number of amine isomers which are structural isomers of the molecular formula `C_(4)H_(11)N`

Explanation

To find the number of amine isomers that are structural isomers of the molecular formula C₄H₁₁N, we will categorize them into primary, secondary, and tertiary amines.

### Step-by-Step Solution:

1. **Understanding the Molecular Formula**:
- The molecular formula C₄H₁₁N indicates that we have 4 carbon atoms, 11 hydrogen atoms, and 1 nitrogen atom.
- Since we are dealing with amines, we know that the nitrogen atom will be bonded to carbon atoms and will not form any rings or double bonds.

**Hint**: Remember that amines can be classified based on the number of carbon groups attached to the nitrogen atom.

2. **Identifying Primary Amines**:
- Primary amines have the amine group (-NH₂) attached to a carbon chain.
- Possible structures:
- **n-Butylamine**: NH₂-CH₂-CH₂-CH₃
- **Isobutylamine**: (CH₃)₂CH-CH₂-NH₂
- **Sec-butylamine**: CH₃-CH(NH₂)-CH₂-CH₃
- **Tert-butylamine**: (CH₃)₃C-NH₂
- Total primary amines = 4.

**Hint**: Draw the carbon chain and attach the -NH₂ group at different positions to visualize primary amines.

3. **Identifying Secondary Amines**:
- Secondary amines have the amine group attached to two carbon chains.
- Possible structures:
- **N,N-Diethylamine**: NH(C₂H₅)₂
- **N-Methyl-N-propylamine**: NH(CH₃)(C₃H₇)
- **Isopropylamine**: (CH₃)₂CH-NH₂
- Total secondary amines = 3.

**Hint**: Consider combinations of two carbon chains attached to the nitrogen atom.

4. **Identifying Tertiary Amines**:
- Tertiary amines have the amine group attached to three carbon chains.
- Possible structure:
- **N,N-Diethyl-N-methylamine**: N(CH₃)(C₂H₅)₂
- Total tertiary amines = 1.

**Hint**: Ensure that nitrogen is bonded to three different carbon groups.

5. **Counting All Isomers**:
- Adding the total number of isomers:
- Primary amines = 4
- Secondary amines = 3
- Tertiary amines = 1
- Total number of amine isomers = 4 + 3 + 1 = 8.

### Final Answer:
The total number of structural isomers (amine isomers) for the molecular formula C₄H₁₁N is **8**.

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