Which of the following halogen cannot from more than one oxoacids ?

Options

A. Bromine
B. Iodine
C. Fluorine
D. Chorine

Answer

To determine which halogen cannot form more than one oxoacid, we need to analyze the ability of each halogen to expand its valency and form different oxoacids. The halogens in question are Fluorine (F), Chlorine (Cl), Bromine (Br), and Iodine (I).

### Step 1: Understanding the Electronic Configuration
1. **Fluorine (F)**: Atomic number 9, electronic configuration is 1s² 2s² 2p⁵.
- Fluorine has no vacant d-orbitals and cannot expand its valency.
- It can only form one oxoacid: HOF (hypofluorous acid).

2. **Chlorine (Cl)**: Atomic number 17, electronic configuration is 1s² 2s² 2p⁶ 3s² 3p⁵.
- Chlorine has vacant d-orbitals (3d) and can expand its valency.
- It can form multiple oxoacids: HClO (hypochlorous acid), HClO₂ (chlorous acid), HClO₃ (chloric acid), HClO₄ (perchloric acid).

3. **Bromine (Br)**: Atomic number 35, electronic configuration is 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 4p⁵.
- Bromine has vacant d-orbitals (4d) and can also expand its valency.
- It can form multiple oxoacids similar to chlorine.

4. **Iodine (I)**: Atomic number 53, electronic configuration is 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 4p⁶ 5s² 5p⁵.
- Iodine has vacant d-orbitals (5d) and can expand its valency.
- It can form multiple oxoacids as well.

### Step 2: Conclusion
Based on the analysis, Fluorine is the only halogen that cannot form more than one oxoacid due to the absence of vacant d-orbitals, which restricts its ability to expand its valency.

**Final Answer**: Fluorine (F) cannot form more than one oxoacid.