A solution containing `Na^(+),NO_(3)^(-), Cl^(-)`, and `SO_(4)^(2-)` ions, all at unit concentrations, is electrolyzed between nickel anode and platinum cathode. As the current is passed through the cell

Options

A. `Ph` of the cathode increases
B. Oxygen is the major product at anode
C. Nickel is deposited at cathode.
D. Chlorine is the major product at anode.

Explanation

To solve the problem of electrolyzing a solution containing `Na^(+)`, `NO3^(-)`, `Cl^(-)`, and `SO4^(2-)` ions between a nickel anode and a platinum cathode, we need to analyze the reactions occurring at both electrodes.

### Step-by-Step Solution:

1. **Identify the Electrolytic Cell Components**:
- The electrolytic cell consists of a nickel anode and a platinum cathode.
- The solution contains the following ions: `Na^(+)`, `NO3^(-)`, `Cl^(-)`, and `SO4^(2-)`.

2. **Determine the Reduction Reaction at the Cathode**:
- At the cathode, reduction occurs. The possible species that can be reduced are:
- `Na^(+)` to `Na`
- `H2O` to `H2` (producing hydroxide ions)
- `NO3^(-)` to some reduced form
- However, the reduction of water to produce hydrogen gas and hydroxide ions is more favorable in this case. The reaction is:
\[ 2H2O + 2e^- \rightarrow H2 + 2OH^- \]
- This reaction increases the concentration of `OH^-` ions, leading to an increase in pH.

3. **Determine the Oxidation Reaction at the Anode**:
- At the anode, oxidation occurs. The possible species that can be oxidized are:
- `Cl^(-)` to `Cl2`
- `SO4^(2-)` and `NO3^(-)` are less likely to be oxidized under these conditions.
- The oxidation of chloride ions is favored, and the reaction is:
\[ 2Cl^- \rightarrow Cl2 + 2e^- \]
- Chlorine gas is produced at the anode.

4. **Conclude the Changes in the Cell**:
- The increase in `OH^-` ions at the cathode leads to an increase in pH, making the solution more basic.
- Chlorine gas is produced at the anode as a result of the oxidation of chloride ions.

### Final Statements:
- The pH of the cathode increases due to the production of hydroxide ions.
- Chlorine gas is produced at the anode from the oxidation of chloride ions.

### Correct Options:
- Statement A: The pH of the cathode increases.
- Statement D: Chlorine gas is produced at the anode.