Molten sodium chloride and sodium chloride dissolved in water .

Explanation

**Step-by-Step Solution:**

1. **Understanding the Electrolysis Process:**
- Electrolysis is a chemical process that uses electricity to break down compounds. In this case, we are looking at the electrolysis of sodium chloride (NaCl) in two different states: molten and dissolved in water.

2. **Electrolysis of Molten Sodium Chloride:**
- When sodium chloride is melted, it dissociates into its ions: Na⁺ (sodium ions) and Cl⁻ (chloride ions).
- At the **negative electrode (cathode)**, the sodium ions (Na⁺) are attracted and gain electrons to form sodium metal (Na).
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