The two aqueous solutions, `A (AgNO_3)` and `B` (LiCI), were electrolysed using Pt electrodes. The `pH` of the resulting solutions will.

Options

A. increase in A and decrease in B
B. decrease in both
C. decrease in both
D. increase in A and decrease in B

Explanation

To solve the problem regarding the pH of the resulting solutions after electrolysis of AgNO3 (solution A) and LiCl (solution B), we can follow these steps:

### Step 1: Understand the Electrolysis of AgNO3
During the electrolysis of AgNO3, the following reaction occurs:
\[ \text{AgNO}_3 + \text{H}_2\text{O} \rightarrow \text{Ag}^+ + \text{NO}_3^- + \text{H}^+ + \frac{1}{2} \text{O}_2 \]

In this reaction, water is split, producing hydrogen ions (H⁺) and hydroxide ions (OH⁻). The increase in H⁺ concentration will lead to a decrease in pH.

### Step 2: Understand the Electrolysis of LiCl
For the electrolysis of LiCl, the reaction can be summarized as:
\[ \text{LiCl} + \text{H}_2\text{O} \rightarrow \text{Li}^+ + \text{Cl}^- + \text{OH}^- + \frac{1}{2} \text{H}_2 \]

In this case, hydroxide ions (OH⁻) are produced, which will increase the pH of the solution.

### Step 3: Analyze the pH Changes
- In solution A (AgNO3), the production of H⁺ ions will result in a **decrease in pH**.
- In solution B (LiCl), the production of OH⁻ ions will result in an **increase in pH**.

### Step 4: Conclusion
After electrolysis:
- The pH of solution A (AgNO3) will **decrease** due to the increase in H⁺ ions.
- The pH of solution B (LiCl) will **increase** due to the increase in OH⁻ ions.

Thus, the overall effect is that the pH of solution A decreases while the pH of solution B increases.

### Final Answer
The pH of the resulting solutions will show a **decrease in A (AgNO3)** and an **increase in B (LiCl)**.