Which one shows maximum hydrogen bonding ?

Options

A. HF
B. `H_(2)O`
C. `NH_(3)`
D. `CH_(3)OH`

Explanation

To determine which compound shows maximum hydrogen bonding among HF, H2O, NH3, and CH3OH, we can follow these steps:

### Step 1: Understand Hydrogen Bonding
Hydrogen bonding occurs when a hydrogen atom covalently bonded to a highly electronegative atom (like F, O, or N) is attracted to another electronegative atom. The strength of hydrogen bonding is influenced by the electronegativity of the atom to which hydrogen is bonded and the size of that atom.

### Step 2: Identify the Atoms in Each Compound
- **HF**: Hydrogen is bonded to fluorine (F).
- **H2O**: Hydrogen is bonded to oxygen (O).
- **NH3**: Hydrogen is bonded to nitrogen (N).
- **CH3OH**: Hydrogen is bonded to oxygen (O) in the hydroxyl group (-OH).

### Step 3: Compare Electronegativity
Next, we compare the electronegativities of the atoms involved:
- **Fluorine (F)**: Highest electronegativity (around 4.0)
- **Oxygen (O)**: Second highest (around 3.5)
- **Nitrogen (N)**: Lower than oxygen (around 3.0)
- **Carbon (C)**: Lowest among these (around 2.5)

### Step 4: Analyze the Results
Since hydrogen bonding is directly proportional to the electronegativity of the atom bonded to hydrogen, we can conclude:
- HF has the highest electronegativity (F), thus it will have the strongest hydrogen bonding.
- H2O has a high electronegativity (O), but lower than HF.
- NH3 has nitrogen, which has lower electronegativity than both F and O.
- CH3OH has oxygen, similar to H2O, but the presence of carbon reduces its overall hydrogen bonding capability compared to HF.

### Step 5: Conclusion
Based on the analysis, HF (hydrogen fluoride) shows the maximum hydrogen bonding due to the presence of fluorine, the most electronegative element.

### Final Answer
The compound that shows maximum hydrogen bonding is **HF (hydrogen fluoride)**.