Extent of hydrolysis of the following is

Options

A. `PCl_(5) gt SiCl_(4) gt MgCl_(2) gt AlCl_(3)`
B. `AlCl_(3) gt MgCl_(2) gt SiCl_(4) gt PCl_(5)`
C. `SiCl_(4) gt PCl_(5) gt MgCl_(2) gt AlCl_(3)`
D. `PCl_(5) gt SiCl_(4) gt AlCl_(3) gt MgCl_(2)`

Answer

To determine the extent of hydrolysis for the given compounds (PCl5, SiCl4, AlCl3, and MgCl2), we will analyze the oxidation states of the central metal atoms and their implications on hydrolysis.

### Step-by-Step Solution:

1. **Identify the Compounds**: The compounds we need to analyze are PCl5, SiCl4, AlCl3, and MgCl2.

2. **Determine the Oxidation States**:
- For **PCl5**: Phosphorus (P) has an oxidation state of +5. (5 Cl atoms contribute -5, so P must be +5 to balance).
- For **SiCl4**: Silicon (Si) has an oxidation state of +4. (4 Cl atoms contribute -4, so Si must be +4).
- For **AlCl3**: Aluminium (Al) has an oxidation state of +3. (3 Cl atoms contribute -3, so Al must be +3).
- For **MgCl2**: Magnesium (Mg) has an oxidation state of +2. (2 Cl atoms contribute -2, so Mg must be +2).

3. **Analyze the Relationship Between Charge and Hydrolysis**:
- The extent of hydrolysis is directly proportional to the charge of the central atom. Higher charges lead to a greater ability to attract water molecules, resulting in more hydrolysis.
- The charges we have are:
- PCl5: +5
- SiCl4: +4
- AlCl3: +3
- MgCl2: +2

4. **Rank the Compounds Based on Hydrolysis**:
- Since PCl5 has the highest charge (+5), it will undergo the most hydrolysis.
- Following that, SiCl4 (+4) will have a lesser extent of hydrolysis.
- Next is AlCl3 (+3), which will have even less hydrolysis.
- Finally, MgCl2 (+2) will have the least extent of hydrolysis.

5. **Conclusion**:
- The order of hydrolysis from highest to lowest is:
- PCl5 > SiCl4 > AlCl3 > MgCl2

### Final Answer:
The extent of hydrolysis of the compounds is in the order: **PCl5 > SiCl4 > AlCl3 > MgCl2**.