Of the following compounds, which one is the strongest Bronsted acid in an aqueous solution ?

Options

A. `HClO_(3)`
B. `HClO_(2)`
C. HOCl
D. HOBr

Explanation

To determine which of the given compounds is the strongest Bronsted acid in an aqueous solution, we will analyze the acidity of each compound based on the oxidation state of the central atom and the stability of the conjugate base.

### Step-by-Step Solution:

1. **Understand Bronsted Acids**:
- A Bronsted acid is defined as a species that donates a proton (H⁺) in an aqueous solution.

2. **Identify the Compounds**:
- The question provides four oxoacids. We will analyze their structures and oxidation states. Let's denote them as:
- A: HClO3
- B: HClO2
- C: HOCl
- D: HCl

3. **Determine Oxidation States**:
- For each compound, calculate the oxidation state of the central atom (Chlorine, Cl):
- A: In HClO3, Cl has an oxidation state of +5.
- B: In HClO2, Cl has an oxidation state of +3.
- C: In HOCl, Cl has an oxidation state of +1.
- D: In HCl, Cl has an oxidation state of -1.

4. **Assess Acidity Based on Oxidation State**:
- Generally, for oxoacids, the acidity increases with the oxidation state of the central atom. Higher oxidation states lead to more stable conjugate bases due to better charge distribution.
- Therefore, we can rank the acids based on the oxidation states:
- HClO3 (+5) > HClO2 (+3) > HOCl (+1) > HCl (-1).

5. **Stability of Conjugate Bases**:
- The conjugate base of HClO3 (ClO3⁻) is more stable than that of HClO2 (ClO2⁻), which is more stable than HOCl (OCl⁻), and HCl (Cl⁻). This stability is due to the presence of more oxygen atoms that can delocalize the negative charge.

6. **Conclusion**:
- Since HClO3 has the highest oxidation state and the most stable conjugate base, it is the strongest Bronsted acid among the given options.

### Final Answer:
The strongest Bronsted acid in an aqueous solution among the given compounds is **HClO3**.