Hydrogen bonding is strongest in

Options

A. Ethanol
B. Ammonia
C. HF
D. Diethylamine

Answer

To determine which of the given compounds exhibits the strongest hydrogen bonding, we will analyze each option based on the electronegativity of the atoms involved in hydrogen bonding.

### Step-by-Step Solution:

1. **Understanding Hydrogen Bonding**:
Hydrogen bonding occurs when a hydrogen atom is covalently bonded to a highly electronegative atom (like nitrogen, oxygen, or fluorine) and is attracted to another electronegative atom in a different molecule.

**Hint**: Recall that hydrogen bonding involves a hydrogen atom and an electronegative atom.

2. **Identifying Electronegativity**:
The strength of hydrogen bonding is influenced by the electronegativity of the atoms involved. The more electronegative the atom, the stronger the hydrogen bond.

**Hint**: Remember that electronegativity increases across a period and decreases down a group in the periodic table.

3. **Analyzing Each Compound**:
- **Ethanol (C2H5OH)**: The electronegative atom here is oxygen. Oxygen has a moderate electronegativity.
- **Ammonia (NH3)**: The electronegative atom is nitrogen. Nitrogen is less electronegative than oxygen.
- **Hydrogen Fluoride (HF)**: The electronegative atom is fluorine. Fluorine is the most electronegative element in the periodic table.
- **Diethylamine (C4H11N)**: The electronegative atom is nitrogen again, similar to ammonia.

**Hint**: Compare the electronegativities of oxygen, nitrogen, and fluorine to determine which is the highest.

4. **Comparing Electronegativity**:
- Electronegativity values (approximately):
- Fluorine (F) = 4.0
- Oxygen (O) = 3.5
- Nitrogen (N) = 3.0
From these values, we can see that fluorine is the most electronegative.

**Hint**: Use the electronegativity values to rank the atoms involved in hydrogen bonding.

5. **Conclusion**:
Since HF has fluorine, which is the most electronegative, it will form the strongest hydrogen bonds compared to ethanol, ammonia, and diethylamine.

**Final Answer**: The strongest hydrogen bonding is found in **HF (Hydrogen Fluoride)**.