For gold plating, the electrolyte used is

Options

A. `AuCl_(3)`
B. `HAuCl_(4)`
C. `K[Au(CN)_(2)]`
D. None of these

Explanation

To determine the electrolyte used for gold plating, we need to understand the process of gold plating and the chemical involved.

### Step-by-Step Solution:

1. **Understanding Gold Plating**:
- Gold plating is a process where a thin layer of gold is deposited onto the surface of another metal. This is done to enhance appearance, prevent corrosion, and improve conductivity.

2. **Identifying the Electrolyte**:
- The electrolyte used in gold plating typically contains gold ions. The most common form of gold used in plating solutions is gold cyanide.

3. **Chemical Formula**:
- The chemical formula for the gold cyanide complex used in gold plating is \( \text{Au(CN)}_2^- \). This indicates that the gold is in a +1 oxidation state and is complexed with cyanide ions.

4. **Conclusion**:
- Therefore, the electrolyte used for gold plating is a solution of potassium gold cyanide, which can be represented as \( \text{KAu(CN)}_2 \).

### Final Answer:
The electrolyte used for gold plating is potassium gold cyanide, \( \text{KAu(CN)}_2 \).

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