Correct order of boiling points of hydrogen halides is 

Options

A. `HF gt HCI gt HBr gt HI`
B. `HF lt HCl lt HBr lt HI`
C. `HCl lt HBr lt HI lt HF`
D. `HF lt HBr lt HI lt HCl`

Answer

To determine the correct order of boiling points of hydrogen halides (HF, HCl, HBr, HI), we need to analyze the factors that influence boiling points, particularly focusing on bond strength and molecular interactions.

### Step-by-Step Solution:

1. **Identify the Hydrogen Halides**: The hydrogen halides in question are HF (hydrogen fluoride), HCl (hydrogen chloride), HBr (hydrogen bromide), and HI (hydrogen iodide).

2. **Consider Bond Strength**: The boiling point of a substance is influenced by the strength of the bonds between its molecules. Stronger bonds typically lead to higher boiling points because more energy is required to break these bonds.

3. **Analyze the Bond Strength of Each Compound**:
- HF has a strong hydrogen bond due to the high electronegativity of fluorine, which leads to a strong dipole-dipole interaction.
- HCl has a weaker bond compared to HF because chlorine is less electronegative than fluorine.
- HBr has an even weaker bond than HCl, as bromine is less electronegative than chlorine.
- HI has the weakest bond among the four, as iodine is the least electronegative and the largest atom, leading to weaker van der Waals forces.

4. **Order the Bond Strength**: Based on the above analysis, we can order the bond strengths as follows:
- HF > HCl > HBr > HI

5. **Relate Bond Strength to Boiling Points**: Since higher bond strength correlates with higher boiling points, we can conclude that the order of boiling points will be the same as the order of bond strengths.

6. **Final Order of Boiling Points**: Therefore, the correct order of boiling points for the hydrogen halides is:
- **HF > HCl > HBr > HI**

### Conclusion:
The correct order of boiling points of hydrogen halides is HF > HCl > HBr > HI.