The sodium carbonate beat test in which `Na_(2)CO_(3)` is used insteal of borax .it is suitable to chromium and

Options

A. Mn
B. Cu
C. Fe
D. Ni

Answer

### Step-by-Step Solution:

1. **Understanding the Sodium Carbonate Bead Test**:
The sodium carbonate bead test is a qualitative analysis method used to detect certain metal ions by heating sodium carbonate (Na₂CO₃) on a platinum wire and observing the color of the bead formed when the metal salt is added.

2. **Identifying the Metals**:
The question specifies that the sodium carbonate bead test is suitable for chromium. We need to determine which other metal from the given options (manganese, copper, iron, nickel) is also suitable for this test.

3. **Reactions Involved**:
- For **Chromium (Cr)**: When chromium oxide (Cr₂O₃) is heated with sodium carbonate, it forms sodium chromate (Na₂CrO₄) and releases carbon dioxide (CO₂). The resulting sodium chromate gives a characteristic yellow bead.
- For **Manganese (Mn)**: When manganese oxide (MnO) is heated with sodium carbonate, it forms sodium manganate (Na₂MnO₄) and also releases carbon dioxide. The resulting sodium manganate gives a characteristic green bead.

4. **Analyzing the Options**:
- **Manganese**: As discussed, it forms a green bead.
- **Copper**: Typically does not produce a characteristic bead in this test.
- **Iron**: Generally does not yield a specific bead color in this test.
- **Nickel**: Also does not produce a characteristic bead.

5. **Conclusion**:
The sodium carbonate bead test is suitable for both chromium and manganese. Therefore, the correct answer to the question is **manganese**.

### Final Answer:
The sodium carbonate bead test is suitable for **manganese**.

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