How many isomer `C_(4)H_(10)O` give positive iodoform test
(Excluding stereoisomer).

Answer

To determine how many isomers of C₄H₁₀O give a positive iodoform test, we will follow these steps:

### Step 1: Identify the possible isomers of C₄H₁₀O
The molecular formula C₄H₁₀O can represent various types of compounds, including alcohols and ethers. We need to consider the structural isomers that can be formed.

### Step 2: Classify the isomers
1. **Alcohols**:
- 1-butanol (CH₃-CH₂-CH₂-CH₂OH)
- 2-butanol (CH₃-CH(OH)-CH₂-CH₃)
- 2-methyl-1-propanol (tert-butanol)
- 2-methyl-2-propanol (CH₃-C(OH)(CH₃)-CH₃)

2. **Ethers**:
- Diethyl ether (CH₃-CH₂-O-CH₂-CH₃)
- Methyl propyl ether (CH₃-O-CH₂-CH₂-CH₃)
- Ethyl methyl ether (CH₃-CH₂-O-CH₃)

### Step 3: Analyze which isomers give a positive iodoform test
The iodoform test is positive for:
- Methyl ketones (R-CO-CH₃)
- Secondary alcohols that have a methyl group adjacent to the hydroxyl group (R-CHOH-CH₃)
- Ethanol (an exception)

From the isomers identified:
- **1-butanol**: Does not give a positive iodoform test (primary alcohol).
- **2-butanol**: Gives a positive iodoform test (secondary alcohol with a methyl group).
- **2-methyl-1-propanol**: Does not give a positive iodoform test (primary alcohol).
- **2-methyl-2-propanol**: Does not give a positive iodoform test (tertiary alcohol).
- **Diethyl ether**: Does not give a positive iodoform test (ether).
- **Methyl propyl ether**: Does not give a positive iodoform test (ether).
- **Ethyl methyl ether**: Does not give a positive iodoform test (ether).

### Step 4: Conclusion
Only **2-butanol** gives a positive iodoform test. Therefore, the total number of isomers of C₄H₁₀O that give a positive iodoform test is **1**.

### Final Answer
**1 isomer of C₄H₁₀O gives a positive iodoform test.**

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