Which of the following forms salt like `KHX_(2)` ?

Options

A. HF
B. HCl
C. HBr
D. HI

Explanation

To determine which of the given compounds forms a salt like KHX₂, we need to analyze the properties of the compounds provided: HF, HCl, HBr, and HI.

### Step-by-Step Solution:

1. **Understanding the Structure of KHX₂**:
- KHX₂ represents a salt where K⁺ (potassium ion) is combined with an anion (HX₂). The anion in this case is derived from a hydrogen halide.

2. **Analyzing the Given Compounds**:
- The compounds provided are HF (hydrofluoric acid), HCl (hydrochloric acid), HBr (hydrobromic acid), and HI (hydroiodic acid).

3. **Electronegativity Consideration**:
- Electronegativity decreases as we move down the group in the periodic table. Fluorine is the most electronegative element, followed by chlorine, bromine, and iodine.
- HF has the highest electronegativity, which leads to strong hydrogen bonding.

4. **Formation of Anions**:
- In the case of HF, the strong hydrogen bonding allows the formation of the anion FHF⁻. This anion can combine with K⁺ to form KHF₂.
- For HCl, HBr, and HI, the electronegativity is lower, and they do not form similar anions that can bond with K⁺ in the same way as HF does.

5. **Conclusion**:
- Among the given compounds, only HF can form a salt like KHX₂ (specifically KHF₂) due to its ability to form the anion FHF⁻ through strong hydrogen bonding.

### Final Answer:
The compound that forms a salt like KHX₂ is **HF**.