Magnesium uranyl test is used for

Options

A. Sodium
B. Potassium
C. Rubidium
D. Caesium

Explanation

**Step-by-Step Solution:**

1. **Understanding the Magnesium Uranyl Test**: The magnesium uranyl test is a qualitative analysis method used to detect the presence of sodium ions in a solution.

2. **Chemical Reaction Involved**: In this test, sodium metal is reacted with uranyl acetate (UO2(CH3COO)2) and magnesium acetate (Mg(CH3COO)2).

3. **Formation of the Product**: When sodium is added to the uranyl acetate in the presence of magnesium acetate, a compound known as sodium magnesium uranyl acetate is formed. The chemical formula for this compound can be represented as NaMg(UO2(CH3COO)2)2.

4. **Observation of the Result**: The key observation in this test is the formation of a yellow precipitate. The appearance of this yellow precipitate indicates the presence of sodium ions in the solution.

5. **Conclusion**: Since the magnesium uranyl test is specifically used to detect sodium, the correct answer to the question is sodium.

**Final Answer**: The magnesium uranyl test is used for detecting sodium (Option A).

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