`Mg_(2)C_(3)` possess which of the following characteristics?

Options

A. Is called magnesium allylide.
B. It contain `Mg^(2+) and C_(3)^(4-)` ions.
C. It on hydrolysis gives propyne.
D. All of these

Explanation

To determine the characteristics of magnesium carbide (Mg₂C₃), we can analyze its properties and reactions systematically.

### Step-by-Step Solution:

1. **Identify the Compound**:
- Magnesium carbide is represented as Mg₂C₃. It is a compound formed from magnesium (Mg) and carbon (C).

2. **Composition of Magnesium Carbide**:
- The formula Mg₂C₃ indicates that it contains two magnesium ions (Mg²⁺) and three carbon atoms (C). The carbon atoms in this compound are in the form of carbide.

3. **Hydrolysis Reaction**:
- When magnesium carbide is subjected to hydrolysis (reaction with water), it produces propyne (an alkyne) and magnesium hydroxide (Mg(OH)₂). The reaction can be summarized as:
\[ \text{Mg}_2\text{C}_3 + 4\text{H}_2\text{O} \rightarrow 2\text{Mg(OH)}_2 + \text{C}_3\text{H}_4 \]
- Here, C₃H₄ represents propyne.

4. **Properties of Magnesium Carbide**:
- Magnesium carbide is insoluble in water, which is a characteristic of many metal carbides.
- It is known as magnesium allide, which is relevant in the context of its usage in organic synthesis.

5. **Conclusion**:
- Based on the above points, we can conclude that magnesium carbide (Mg₂C₃) possesses the following characteristics:
- It is known as magnesium allide.
- It produces propyne upon hydrolysis.
- It contains magnesium ions and carbon atoms, confirming the composition.

### Final Answer:
The correct answer is "all of these" as it encompasses all the characteristics mentioned.

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