Of the given anions, the strongest Bronsted base is

Options

A. (a) `ClO^(Theta)`
B. (b) `ClO_(2)^(Theta)`
C. (c) `ClO_(3)^(Theta)`
D. (d) `ClO_(4)^(Theta)`

Explanation

To determine which of the given anions is the strongest Brønsted base, we need to analyze the anions provided: ClO⁻, ClO₂⁻, ClO₃⁻, and ClO₄⁻. A Brønsted base is defined as a species that can accept a proton (H⁺ ion).

### Step-by-Step Solution:

1. **Understanding Brønsted Bases**:
- A Brønsted base is a substance that can accept protons (H⁺ ions). Therefore, we need to consider how each anion behaves when it accepts a proton.

2. **Formation of Acids**:
- When each anion accepts a proton, they form the corresponding acids:
- ClO⁻ → HClO (hypochlorous acid)
- ClO₂⁻ → HClO₂ (chlorous acid)
- ClO₃⁻ → HClO₃ (chloric acid)
- ClO₄⁻ → HClO₄ (perchloric acid)

3. **Determining Oxidation States**:
- To understand the acidic strength of these acids, we need to calculate the oxidation state of chlorine in each:
- In HClO: Cl is +1
- In HClO₂: Cl is +3
- In HClO₃: Cl is +5
- In HClO₄: Cl is +7

4. **Acidic Strength and Oxidation State**:
- The acidic strength of these acids increases with the oxidation state of chlorine. Thus, the order of acidic strength is:
- HClO₄ > HClO₃ > HClO₂ > HClO

5. **Analyzing the Bases**:
- The stronger the acid, the weaker its conjugate base. Therefore, since HClO₄ is the strongest acid, ClO₄⁻ is the weakest base. Conversely, HClO is the weakest acid, making ClO⁻ the strongest base.

6. **Conclusion**:
- Since ClO⁻ has the least tendency to donate H⁺ ions (it is the least acidic), it has the highest tendency to accept H⁺ ions, making it the strongest Brønsted base among the given anions.

### Final Answer:
The strongest Brønsted base among the given anions is **ClO⁻**.