Out of `HF, HCl, HBr and HI`, the lowest boiling point is of …………and highest boiling point is of ……………….

Explanation

To determine the lowest and highest boiling points among HF, HCl, HBr, and HI, we can follow these steps:

### Step 1: Understand the Factors Affecting Boiling Points
Boiling points of substances are influenced by intermolecular forces, molecular weight, and the presence of hydrogen bonding.

### Step 2: Analyze the Compounds
- **HF (Hydrogen Fluoride)**: This molecule can form hydrogen bonds due to the highly electronegative fluorine atom.
- **HCl (Hydrogen Chloride)**: This molecule primarily exhibits van der Waals forces, which are weaker than hydrogen bonds.
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