Name the halogen which forms only one oxo acid and also write the formula of the oxo acid.

Explanation

To solve the question, we need to identify the halogen that forms only one oxoacid and then write the formula of that oxoacid.

### Step-by-Step Solution:

1. **Identify the Halogens**: The halogens are fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At).

2. **Research Oxoacids of Halogens**:
- Fluorine forms hypofluorous acid (HOF) and fluoric acid (HFO₃).
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