Identify the reagent that can be used to detect phosphate radical

Options

A. Neutral `FeCl_(3)`
B. Magnesia mixture
C. Acidified `KMnO_4`.
D. Conc.` H_2SO_4`

Answer

To identify the reagent that can be used to detect the phosphate radical, we will follow these steps:

### Step-by-Step Solution:

1. **Understanding the Phosphate Radical**:
- The phosphate radical is represented as \( \text{PO}_4^{3-} \). It is important to know that we are looking for a reagent that can react with this radical to form a detectable product.

2. **Reviewing the Given Options**:
- The options provided are:
- Neutral FeCl3
- Magnesia Mixture
- Mixture
- Acidified KmnO4
- Concentrated H2SO4

3. **Identifying the Correct Reagent**:
- Among the options, we need to identify which reagent is known for its ability to form a precipitate with phosphate ions.
- The Magnesia Mixture is known to be effective in detecting phosphate radicals.

4. **Understanding Magnesia Mixture**:
- Magnesia Mixture is an aqueous mixture that contains:
- Ammonium Chloride (\( \text{NH}_4\text{Cl} \))
- Magnesium Sulfate (\( \text{MgSO}_4 \))
- Ammonia (\( \text{NH}_3 \))
- This mixture is specifically used to detect phosphate ions.

5. **Reaction with Phosphate**:
- When soluble phosphate reacts with Magnesia Mixture, it forms a white precipitate of Magnesium Ammonium Phosphate (\( \text{MgNH}_4\text{PO}_4 \cdot 6\text{H}_2\text{O} \)).
- The formation of this white precipitate indicates the presence of phosphate ions.

6. **Conclusion**:
- Therefore, the reagent that can be used to detect the phosphate radical is **Magnesia Mixture**.

### Final Answer:
- The reagent that can be used to detect the phosphate radical is **Magnesia Mixture**.