Electrolysis of `KCl. MgCl_2 . 6H_2O` gives:
potassium only
magnesium only
magnesium and chlorine
potassium and magnesium.

Options

A. potassium only
B. magnesium only
C. magnesium and chlorine
D. potassium and magnesium.

Explanation

To solve the question regarding the electrolysis of KCl·MgCl₂·6H₂O, we can follow these steps:

### Step 1: Understand the Components
The compound KCl·MgCl₂·6H₂O consists of potassium chloride (KCl) and magnesium chloride (MgCl₂) in a hydrated form. During electrolysis, these compounds will dissociate into their respective ions.

### Step 2: Identify the Ions
When KCl and MgCl₂ dissolve in water, they dissociate into:
- K⁺ (potassium ions)
- Cl⁻ (chloride ions)
- Mg²⁺ (magnesium ions)

### Step 3: Analyze the Electrolysis Process
During electrolysis, the following reactions can occur:
- At the cathode (reduction), cations (K⁺ and Mg²⁺) will gain electrons.
- At the anode (oxidation), anions (Cl⁻) will lose electrons.

### Step 4: Compare Reduction Potentials
The reduction potentials of the ions are crucial in determining which will be reduced:
- The standard reduction potential for K⁺ + e⁻ → K is approximately -2.93 V.
- The standard reduction potential for Mg²⁺ + 2e⁻ → Mg is approximately -2.37 V.

Since the reduction potential of Mg²⁺ is higher (less negative) than that of K⁺, magnesium ions will be preferentially reduced at the cathode.

### Step 5: Determine the Products
- At the cathode, magnesium (Mg) will be produced from Mg²⁺ ions.
- At the anode, chloride ions (Cl⁻) will be oxidized to produce chlorine gas (Cl₂).

### Conclusion
Thus, the electrolysis of KCl·MgCl₂·6H₂O will yield magnesium and chlorine gas as the products.

### Final Answer
The correct option is: **Magnesium and Chlorine.**

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