Which oxychloride has maximum pH?

Options

A. `NaCIO`
B. `NaCIO_(2)`
C. `NaCIO_(3)`
D. `NaCIO_(4)`

Answer

To determine which oxychloride has the maximum pH, we need to analyze the hydrolysis of the oxychlorides formed from sodium hydroxide (NaOH) and various hypochlorous acids (HClO, HClO2, HClO3, HClO4).

### Step-by-Step Solution:

1. **Identify the Oxychlorides**:
The oxychlorides in question are formed by combining NaOH with:
- HClO (hypochlorous acid)
- HClO2 (chlorous acid)
- HClO3 (chloric acid)
- HClO4 (perchloric acid)

2. **Determine the Strength of Acids**:
The strength of the acids decreases in the following order:
- HClO4 > HClO3 > HClO2 > HClO
HClO4 is the strongest acid, and HClO is the weakest.

3. **Understand Hydrolysis**:
- Hydrolysis occurs when a salt reacts with water to produce an acidic or basic solution.
- The cation from NaOH (Na⁺) does not hydrolyze as it comes from a strong base, while the anions (ClO⁻, ClO2⁻, ClO3⁻, ClO4⁻) will undergo hydrolysis depending on the strength of the corresponding acid.

4. **Analyze Hydrolysis of Each Anion**:
- **ClO⁻**: Hydrolyzes to form HClO (weak acid) and OH⁻, increasing pH.
- **ClO2⁻**: Hydrolyzes to form HClO2 (weak acid) and OH⁻, increasing pH but less than ClO⁻.
- **ClO3⁻**: Hydrolyzes to form HClO3 (strong acid), leading to minimal hydrolysis and a lower pH.
- **ClO4⁻**: Does not hydrolyze as it forms HClO4 (strong acid), resulting in no increase in pH.

5. **Conclusion**:
The oxychloride that produces the highest concentration of OH⁻ ions through hydrolysis will have the maximum pH. Since ClO⁻ hydrolyzes to produce OH⁻ and is derived from the weakest acid (HClO), it will lead to the highest pH.

Thus, the oxychloride with the maximum pH is the one derived from **NaOH and HClO**, which is sodium hypochlorite (NaClO).

### Final Answer:
**The oxychloride with maximum pH is NaClO (sodium hypochlorite).**