Which of the following reaction will not take place?

Options

A. `Zn + FeSO_(4) to ZnSO_(4) + H_(2) O`
B. `2K1 + C1_(2) to 2KC1 + I_(2)`
C. `Zn + MgSO_(4) to ZnSO_(4) + Mg`
D. `Mg + CuSO_(4) to MgSO_(4) + Cu`

Explanation

To determine which of the given reactions will not take place, we need to analyze each reaction based on the reactivity of the metals involved. Displacement reactions occur when a more reactive metal displaces a less reactive metal from its compound. We will refer to the electrochemical series to assess the reactivity of the metals.

### Step-by-Step Solution:

1. **Identify the Reactions**:
We have four reactions to analyze:
- Reaction 1: Zinc displaces Iron (Zn + FeSO₄ → ZnSO₄ + Fe)
- Reaction 2: Chlorine displaces Iodine (Cl₂ + 2KI → 2KCl + I₂)
- Reaction 3: Zinc displaces Magnesium (Zn + MgSO₄ → ZnSO₄ + Mg)
- Reaction 4: Magnesium displaces Copper (Mg + CuSO₄ → MgSO₄ + Cu)

2. **Check Reactivity of Metals**:
- **Zinc vs. Iron**: Zinc is more reactive than Iron (Zn > Fe). Therefore, this reaction will take place.
- **Chlorine vs. Iodine**: Chlorine is more reactive than Iodine (Cl > I). Therefore, this reaction will take place.
- **Zinc vs. Magnesium**: Zinc is less reactive than Magnesium (Zn < Mg). Therefore, this reaction will NOT take place.
- **Magnesium vs. Copper**: Magnesium is more reactive than Copper (Mg > Cu). Therefore, this reaction will take place.

3. **Conclusion**:
Based on the analysis, the reaction that will not take place is the third one where Zinc attempts to displace Magnesium.

### Final Answer:
The reaction that will not take place is **Zinc displacing Magnesium**.

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