When `NaCl` is dissolved in water the sodium ion becomes

Options

A. Oxidation
B. Reduction
C. Hydrolysis
D. Hydration

Answer

To solve the question "When NaCl is dissolved in water, the sodium ion becomes," we can follow these steps:

### Step 1: Understand the Dissolution of NaCl
When sodium chloride (NaCl) is dissolved in water, it dissociates into its constituent ions. The equation for this process can be represented as:
\[ \text{NaCl (s)} \rightarrow \text{Na}^+ (aq) + \text{Cl}^- (aq) \]

### Step 2: Identify the Sodium Ion
In the dissolution process, the sodium ion (\(\text{Na}^+\)) is released into the solution.

### Step 3: Analyze the Options
We have the following options to consider:
- Oxidation
- Reduction
- Hydrolysis
- Hydration

### Step 4: Determine the Correct Process
The sodium ion (\(\text{Na}^+\)) does not undergo oxidation or reduction in this process. Instead, it interacts with the water molecules. This interaction is known as hydration, where water molecules surround the sodium ion, stabilizing it in the solution.

### Step 5: Conclusion
Therefore, when NaCl is dissolved in water, the sodium ion becomes hydrated. The correct answer is:
**Hydration**

### Final Answer
The sodium ion becomes hydrated when NaCl is dissolved in water.

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