The electrochemical cell representing the given reaction
`Ni(s)+Cu^(2+) rarr Ni^(2+)+Cu(s)`

Options

A. `Ni(s)|Cu^(2+)||Ni^(2+)|Cu(s)`
B. `Ni(s)|Ni^(2+)||Cu^(2+)|Cu`
C. `Cu(s)|Cu^(2+)||Ni(s)|Ni^(2+)`
D. `Cu(s)|Cu^(2+)||Ni^(2+)|Ni(s)`

Answer

To represent the electrochemical cell for the reaction \( \text{Ni(s)} + \text{Cu}^{2+} \rightarrow \text{Ni}^{2+} + \text{Cu(s)} \), we need to follow these steps:

### Step 1: Identify the Half-Reactions
The first step is to identify the oxidation and reduction half-reactions from the overall reaction.

- **Oxidation Half-Reaction**: Nickel (Ni) is oxidized to nickel ions (\( \text{Ni}^{2+} \)):
\[ \text{Ni(s)} \rightarrow \text{Ni}^{2+} + 2e^- \]

- **Reduction Half-Reaction**: Copper ions (\( \text{Cu}^{2+} \)) are reduced to copper (Cu):
\[ \text{Cu}^{2+} + 2e^- \rightarrow \text{Cu(s)} \]

### Step 2: Write the Cell Notation
The cell notation is a shorthand way of representing the electrochemical cell. It follows the format:
\[ \text{Anode} | \text{Anode Solution} || \text{Cathode Solution} | \text{Cathode} \]

- **Anode**: The anode is where oxidation occurs. In this case, nickel is oxidized. Therefore, the anode side will be:
\[ \text{Ni(s)} | \text{Ni}^{2+}(aq) \]

- **Cathode**: The cathode is where reduction occurs. In this case, copper ions are reduced. Therefore, the cathode side will be:
\[ \text{Cu}^{2+}(aq) | \text{Cu(s)} \]

### Step 3: Combine the Notations
Now, we combine the anode and cathode notations with a double vertical line (||) to represent the salt bridge:
\[ \text{Ni(s)} | \text{Ni}^{2+}(aq) || \text{Cu}^{2+}(aq) | \text{Cu(s)} \]

### Final Cell Notation
The final cell notation for the electrochemical cell representing the reaction is:
\[ \text{Ni(s)} | \text{Ni}^{2+}(aq) || \text{Cu}^{2+}(aq) | \text{Cu(s)} \]

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