In the extraction of magnesium from magnesium chloride, sodium chloride helps

Options

A. lower the conductivity of `MgCl_(2)`
B. rise the conductivity of `MgCl_(2)`
C. lower the melting point of `MgCl_(2)`
D. `Change the solid state structure of `MgCl_(2)`

Answer

To solve the question regarding the role of sodium chloride (NaCl) in the extraction of magnesium from magnesium chloride (MgCl2), we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding the Process**: The extraction of magnesium from magnesium chloride typically involves electrolysis. In this process, an electric current is passed through a molten or dissolved electrolyte to cause a chemical reaction.

2. **Role of Sodium Chloride**: Sodium chloride is added to the magnesium chloride during the electrolysis process. It serves two main purposes:
- **Increase Conductivity**: NaCl increases the overall conductivity of the electrolyte solution. This is crucial because higher conductivity allows for more efficient passage of electric current, which is necessary for the electrolysis to occur effectively.
- **Lower Melting Point**: NaCl also helps to lower the melting point of magnesium chloride. By doing so, it makes it easier to melt the MgCl2, which is important because the electrolysis process requires the magnesium chloride to be in a molten state for the ions to move freely.

3. **Conclusion**: Therefore, sodium chloride plays a vital role in the extraction of magnesium from magnesium chloride by enhancing conductivity and lowering the melting point of the electrolyte.

### Final Answer:
In the extraction of magnesium from magnesium chloride, sodium chloride helps by increasing the conductivity of the electrolyte and lowering the melting point of magnesium chloride.

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