`Mg` is not precipitate in group V because

Options

A. `MgCO_(3)` in soluble in `H_(2)O`
B. `MgCO_(3)` in soluble in `NH_(4)CI`
C. `MgCO_(3)` in soluble in `NH_(4)OH`
D. All

Answer

To answer the question "Why is Mg not precipitated in group V?", we can break down the explanation into clear steps:

### Step-by-Step Solution:

1. **Understanding Group V Precipitation**:
- Group V in qualitative analysis typically includes ions that do not precipitate with common reagents used in the analysis.

2. **Identifying Magnesium**:
- Magnesium (Mg) is an alkaline earth metal and is part of the s-block elements in the periodic table.

3. **Solubility of Magnesium Compounds**:
- Magnesium carbonate (MgCO₃) is a compound that can be formed during the analysis. However, it is important to note that magnesium carbonate is soluble in water.

4. **Ksp (Solubility Product Constant)**:
- The solubility product constant (Ksp) is a measure of how much of a compound can dissolve in water. A high Ksp value indicates that the compound is more soluble.

5. **High Ksp of Magnesium Carbonate**:
- The Ksp of magnesium carbonate is relatively high. This means that when magnesium ions (Mg²⁺) and carbonate ions (CO₃²⁻) are present, they do not readily precipitate out of solution because the tendency to remain dissolved is strong.

6. **Comparison with Group V Ions**:
- In contrast, the Ksp values of the compounds formed by the ions in group V are generally much lower. This means that these ions are more likely to precipitate when mixed with reagents.

7. **Conclusion**:
- Therefore, the reason magnesium does not precipitate in group V is primarily due to the high Ksp of magnesium carbonate, which allows it to remain soluble in solution.

### Final Answer:
Magnesium is not precipitated in group V because the Ksp of magnesium carbonate is high, indicating that it remains soluble in water.

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