Identify B in the above reaction.
`Ca(OH)_(2) overset(Cl_(2)-H_(2)O)to A overset("Auto Oxidation")to CaCl_(2)+B`

Options

A. `CaOCl_(2)`
B. `Ca(ClO_(3))_(2)`
C. `Ca(OH)_(2)`
D. `Ca(ClO_(2))_(2)`

Explanation

To identify B in the given reaction, we will analyze the steps involved in the reaction of calcium hydroxide with chlorine and water.

### Step-by-Step Solution:

1. **Identify the Initial Reactants**:
The reaction starts with calcium hydroxide, which is represented as \( \text{Ca(OH)}_2 \).

2. **Reaction with Chlorine and Water**:
When calcium hydroxide reacts with chlorine (\( \text{Cl}_2 \)) and water (\( \text{H}_2\text{O} \)), it produces calcium oxychloride, which is represented as \( \text{Ca(OCl)}_2 \). This product is labeled as A in the reaction.

\[ \text{Ca(OH)}_2 + \text{Cl}_2 + \text{H}_2\text{O} \rightarrow \text{Ca(OCl)}_2 \quad \text{(A)} \]

3. **Auto-Oxidation Process**:
The next step involves auto-oxidation of the product A (\( \text{Ca(OCl)}_2 \)). During this process, calcium oxychloride undergoes further reactions leading to the formation of calcium chloride (\( \text{CaCl}_2 \)) and another product.

4. **Identify the Second Product (B)**:
The auto-oxidation of \( \text{Ca(OCl)}_2 \) results in the formation of calcium chloride and calcium chlorate. The calcium chlorate is represented as \( \text{Ca(ClO}_3\text{)}_2 \).

\[ \text{Ca(OCl)}_2 \rightarrow \text{CaCl}_2 + \text{Ca(ClO}_3\text{)}_2 \quad \text{(B)} \]

5. **Conclusion**:
Therefore, the substance B that is formed in the reaction is \( \text{Ca(ClO}_3\text{)}_2 \), which is calcium chlorate.

### Final Answer:
B = \( \text{Ca(ClO}_3\text{)}_2 \)

---