Consider the following statements and choose the correct option
(i) Addition of `CdCl_(2)` to the Crystals of `AgCl` will produce cation vacancy
(ii) Additon of `NaCl` to the crystals of `AgCl` would not produce cation vacancy

Options

A. both (i) and (ii) are true
B. Only (i) is true
C. Only (ii) is true
D. Both are false

Answer

To solve the question, we need to analyze the two statements provided about the addition of `CdCl2` and `NaCl` to the crystals of `AgCl`.

### Step 1: Analyze the first statement
The first statement claims that the addition of `CdCl2` to the crystals of `AgCl` will produce a cation vacancy.

- **Understanding the ions involved**:
- `AgCl` consists of `Ag+` (silver cation) and `Cl-` (chloride anion).
- `CdCl2` consists of `Cd2+` (cadmium cation) and `Cl-` (chloride anion).

- **Charge considerations**:
- The `Ag+` has a +1 charge, while `Cd2+` has a +2 charge.
- To maintain charge balance when `Cd2+` is introduced, it will replace two `Ag+` ions because one `Cd2+` can balance the charge of two `Ag+` ions.

- **Result of the addition**:
- When `Cd2+` replaces two `Ag+` ions, it creates a vacancy for the `Ag+` ions that were removed. This means there are now cation vacancies in the crystal structure.

Thus, the first statement is **true**.

### Step 2: Analyze the second statement
The second statement claims that the addition of `NaCl` to the crystals of `AgCl` would not produce a cation vacancy.

- **Understanding the ions involved**:
- `NaCl` consists of `Na+` (sodium cation) and `Cl-` (chloride anion).

- **Charge considerations**:
- Both `Na+` and `Ag+` have a +1 charge.

- **Result of the addition**:
- When `NaCl` is added to `AgCl`, the `Na+` can replace `Ag+` in a 1:1 ratio. For every `Na+` added, one `Ag+` is replaced.
- Since the charges are the same and the number of ions remains balanced, there are no vacancies created in the crystal structure.

Thus, the second statement is also **true**.

### Conclusion
Both statements are correct. Therefore, the correct option is that both statements are true.

### Final Answer:
Both statements (i) and (ii) are true.

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