Fenton's reagent is :

Options

A. `FeSO_(4)+H_(2)O_(2)`
B. `HgSO_(4) + H_(2)O_(2)`
C. `FeSO_(4) + H_(2)O`
D. None of these

Explanation

To determine what Fenton's reagent is, we will analyze the options provided and understand the composition of Fenton's reagent.

### Step-by-Step Solution:

1. **Understanding Fenton's Reagent**:
Fenton's reagent is a well-known chemical solution used in various applications, particularly in the field of environmental chemistry for the oxidation of organic pollutants.

2. **Identifying the Components**:
The key components of Fenton's reagent are:
- **Hydrogen Peroxide (H2O2)**: This is a strong oxidizing agent.
- **Iron(II) Sulfate (FeSO4)**: This acts as a catalyst in the reaction.

3. **Analyzing the Options**:
- **Option A**: Iron Sulfate plus Hydrogen Peroxide (FeSO4 + H2O2)
- **Option B**: Mercury Sulfate plus Hydrogen Peroxide (HgSO4 + H2O2)
- **Option C**: Iron Sulfate plus Water (FeSO4 + H2O)
- **Option D**: None of these

4. **Matching with Fenton's Reagent**:
- From our understanding, Fenton's reagent is specifically made up of Iron(II) Sulfate and Hydrogen Peroxide.
- Therefore, **Option A (FeSO4 + H2O2)** is the correct answer.

5. **Conclusion**:
Fenton's reagent is indeed a solution of Iron Sulfate and Hydrogen Peroxide, which is used primarily for oxidizing contaminants in wastewater.

### Final Answer:
Fenton's reagent is Iron Sulfate plus Hydrogen Peroxide (FeSO4 + H2O2). The correct option is **A**.

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