The correct order of the stoichiometries of `AgCl` formed when `AgNO_3` in excess is treated with the complexes: `CoCl_(3).6NH_3, CoCl_(3).5NH_3, CoCl_(3). 4NH_3` respectively is:

Options

A. 1 AgCl, 3AgCl, 2AgCl
B. 3AgCl, 1 AgCl, 2AgCl
C. 3AgCl, 2AgCl , 1AgCl
D. 2AgCl , 3AgCl, 1 AgCl

Explanation

To determine the correct order of the stoichiometries of AgCl formed when AgNO3 in excess is treated with the complexes CoCl3·6NH3, CoCl3·5NH3, and CoCl3·4NH3, we can analyze each complex step by step.

### Step 1: Analyze CoCl3·6NH3
1. **Identify the coordination number**: The coordination number of cobalt in CoCl3·6NH3 is 6.
2. **Write the general formula**: The complex can be represented as [Co(NH3)6]Cl3.
3. **Determine the number of Cl ions**: There are 3 Cl ions available for reaction with AgNO3.
4. **Reaction with AgNO3**: When AgNO3 is added, it will react with all 3 Cl ions to form AgCl.
5. **Stoichiometry of AgCl formed**: Therefore, 3 moles of AgCl will be formed.

### Step 2: Analyze CoCl3·5NH3
1. **Identify the coordination number**: The coordination number remains 6.
2. **Write the general formula**: The complex can be represented as [Co(NH3)5Cl]Cl2.
3. **Determine the number of Cl ions**: There are 2 Cl ions available for reaction with AgNO3.
4. **Reaction with AgNO3**: When AgNO3 is added, it will react with the 2 Cl ions to form AgCl.
5. **Stoichiometry of AgCl formed**: Therefore, 2 moles of AgCl will be formed.

### Step 3: Analyze CoCl3·4NH3
1. **Identify the coordination number**: The coordination number is still 6.
2. **Write the general formula**: The complex can be represented as [Co(NH3)4Cl2]Cl.
3. **Determine the number of Cl ions**: There is 1 Cl ion available for reaction with AgNO3.
4. **Reaction with AgNO3**: When AgNO3 is added, it will react with the 1 Cl ion to form AgCl.
5. **Stoichiometry of AgCl formed**: Therefore, 1 mole of AgCl will be formed.

### Conclusion
Now, we can summarize the stoichiometries of AgCl formed from each complex:
- From CoCl3·6NH3: 3 moles of AgCl
- From CoCl3·5NH3: 2 moles of AgCl
- From CoCl3·4NH3: 1 mole of AgCl

Thus, the correct order of the stoichiometries of AgCl formed is:
**3 > 2 > 1**

### Final Answer
The correct order of the stoichiometries of AgCl formed is: **3, 2, 1**.