The cell reaction of the galvanic cell:
`Cu(s)|Cu^(2+)(aq)||Hg^(2+)(aq)|Hg(l)` is

Options

A. `Hg+Cu^(2+)rarrHg^(2+)+ Cu`
B. `Hg+Cu^(2+)rarrCu^(+)+Hg^(+)`
C. `Cu+HgrarrCuHg`
D. `Cu+Hg^(2+)rarrCu^(2+)+Hg`.

Explanation

To determine the cell reaction of the galvanic cell represented by the notation `Cu(s)|Cu^(2+)(aq)||Hg^(2+)(aq)|Hg(l)`, we need to analyze the oxidation and reduction processes occurring at the anode and cathode, respectively.

### Step-by-Step Solution:

1. **Identify the Anode and Cathode:**
- In a galvanic cell, the anode is where oxidation occurs, and the cathode is where reduction occurs.
- Here, the anode is represented by `Cu(s)` and the cathode by `Hg^(2+)(aq)`.

2. **Write the Half-Reaction at the Anode:**
- At the anode, copper (Cu) is oxidized to copper ions (Cu²⁺).
- The half-reaction can be written as:
\[ \text{Cu(s)} \rightarrow \text{Cu}^{2+}(aq) + 2e^- \]
- This indicates that solid copper loses two electrons to form copper ions.

3. **Write the Half-Reaction at the Cathode:**
- At the cathode, mercury ions (Hg²⁺) are reduced to liquid mercury (Hg).
- The half-reaction can be written as:
\[ \text{Hg}^{2+}(aq) + 2e^- \rightarrow \text{Hg(l)} \]
- This indicates that mercury ions gain two electrons to form liquid mercury.

4. **Combine the Half-Reactions:**
- To find the overall cell reaction, we add the two half-reactions together:
\[ \text{Cu(s)} + \text{Hg}^{2+}(aq) \rightarrow \text{Cu}^{2+}(aq) + \text{Hg(l)} \]
- This equation shows that solid copper and mercury ions react to produce copper ions in solution and liquid mercury.

5. **Final Cell Reaction:**
- The final balanced cell reaction is:
\[ \text{Cu(s)} + \text{Hg}^{2+}(aq) \rightarrow \text{Cu}^{2+}(aq) + \text{Hg(l)} \]