Strongest bond is (a) HF (b) HCl (c) HBr (d) HI

Options

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

Answer

To determine which bond is the strongest among HF, HCl, HBr, and HI, we can analyze the bond strength based on the properties of the elements involved.

### Step-by-Step Solution:

1. **Identify the Bonds**: The question provides four compounds: HF (hydrogen fluoride), HCl (hydrogen chloride), HBr (hydrogen bromide), and HI (hydrogen iodide). Each of these compounds consists of a hydrogen atom bonded to a halogen atom.

2. **Consider the Halogens**: The halogens in these compounds are fluorine (F), chlorine (Cl), bromine (Br), and iodine (I). These elements are in Group 17 of the periodic table.

3. **Analyze Atomic Size**: As we move down the group from fluorine to iodine, the size of the atoms increases. Fluorine is the smallest halogen, while iodine is the largest.

4. **Bond Length and Strength**: Generally, shorter bonds are stronger. Since HF has the smallest atomic size (due to fluorine being the smallest halogen), it forms a shorter and stronger bond with hydrogen compared to the other compounds.

5. **Bond Strength Trend**: The bond strength decreases as the size of the halogen increases. Therefore, the order of bond strength from strongest to weakest is:
- HF > HCl > HBr > HI

6. **Conclusion**: Based on the analysis, HF has the strongest bond among the given options.

### Final Answer:
The strongest bond is (a) HF.

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