Among the following, the number of compounds that can react with `PCl_(5)` to give `POCl_(3)` is : `O_(2), CO_(2), SO_(2), H_(2)O, H_(2)SO_(4), P_(4)O_(10)`.

Explanation

To solve the problem of determining how many compounds among the given options can react with \( PCl_5 \) to produce \( POCl_3 \), we will analyze each compound one by one.

### Step-by-Step Solution:

1. **Identify the Compounds**: The compounds given are \( O_2, CO_2, SO_2, H_2O, H_2SO_4, P_4O_{10} \).

2. **Reaction with \( O_2 \)**:
- **Reaction**: \( PCl_5 + O_2 \)
- **Analysis**: No reaction occurs as \( O_2 \) is a stable molecule and does not react with \( PCl_5 \).
- **Conclusion**: Does not produce \( POCl_3 \).

3. **Reaction with \( CO_2 \)**:
- **Reaction**: \( PCl_5 + CO_2 \)
- **Analysis**: \( CO_2 \) is also a stable molecule and cannot break the strong bonds in \( PCl_5 \).
- **Conclusion**: Does not produce \( POCl_3 \).

4. **Reaction with \( SO_2 \)**:
- **Reaction**: \( PCl_5 + SO_2 \)
- **Products**: The reaction produces \( SOCl_2 \) and \( POCl_3 \).
- **Conclusion**: This compound does react to produce \( POCl_3 \).

5. **Reaction with \( H_2O \)**:
- **Reaction**: \( PCl_5 + H_2O \)
- **Products**: The reaction results in \( POCl_3 \) and \( HCl \).
- **Conclusion**: This compound also reacts to produce \( POCl_3 \).

6. **Reaction with \( H_2SO_4 \)**:
- **Reaction**: \( PCl_5 + H_2SO_4 \)
- **Products**: The reaction produces \( SO_2Cl_2 \) and \( POCl_3 \).
- **Conclusion**: This compound reacts to produce \( POCl_3 \).

7. **Reaction with \( P_4O_{10} \)**:
- **Reaction**: \( PCl_5 + P_4O_{10} \)
- **Products**: The reaction produces \( POCl_3 \).
- **Conclusion**: This compound also reacts to produce \( POCl_3 \).

8. **Count the Compounds**:
- The compounds that can react with \( PCl_5 \) to produce \( POCl_3 \) are \( SO_2, H_2O, H_2SO_4, \) and \( P_4O_{10} \).
- Total = 4 compounds.

### Final Answer:
The number of compounds that can react with \( PCl_5 \) to give \( POCl_3 \) is **4**.