Among the following compounds , the strongest acid is:

Options

A. `HC = CH`
B. `C_(6)` H_(6)`
C. `C_(2) H_(6)`
D. `CH_(3)OH`

Explanation

To determine which of the given compounds is the strongest acid, we will analyze the acidic nature of each compound based on the presence of hydrogen atoms and the electronegativity of the atoms to which they are attached.

### Step-by-Step Solution:

1. **Identify the Compounds**: The compounds given are:
- Acetylene (C2H2)
- Benzene (C6H6)
- Ethane (C2H6)
- Methanol (CH3OH)

2. **Understand Acidity**: An acid is a substance that can donate a hydrogen ion (H+) when dissolved in water. The strength of an acid is often related to the stability of the conjugate base formed after the hydrogen ion is lost.

3. **Analyze Each Compound**:
- **Acetylene (C2H2)**: The hydrogen atoms are attached to carbon, which is not very electronegative. Therefore, acetylene is weakly acidic.
- **Benzene (C6H6)**: Similar to acetylene, the hydrogen atoms are attached to carbon. Benzene is also weakly acidic because the hydrogen atoms are not bonded to electronegative atoms.
- **Ethane (C2H6)**: Ethane has hydrogen atoms attached to carbon as well. It is the least acidic among the three hydrocarbons since it does not have any electronegative atoms to stabilize the negative charge after losing H+.
- **Methanol (CH3OH)**: In methanol, the hydrogen is attached to an oxygen atom, which is highly electronegative. This makes methanol more acidic because the conjugate base (CH3O-) is stabilized by the electronegative oxygen atom.

4. **Compare the Acidity**:
- Acetylene, benzene, and ethane have hydrogen atoms bonded to carbon, making them weak acids.
- Methanol, with hydrogen bonded to oxygen, is significantly more acidic due to the electronegativity of oxygen.

5. **Conclusion**: Among the given compounds, methanol (CH3OH) is the strongest acid.

### Final Answer:
The strongest acid among the given compounds is **Methanol (CH3OH)**.