Magnesium hydroxide is _____

Options

A. Monoacidic alkali
B. Diacidic alkali
C. Triacidic alkali
D. All of these

Explanation

To determine what type of alkali magnesium hydroxide is, we need to analyze its chemical structure and the number of hydroxide ions (OH⁻) it can donate in an aqueous solution.

### Step-by-Step Solution:

1. **Identify the Chemical Formula**:
The chemical formula for magnesium hydroxide is Mg(OH)₂.

2. **Understand the Composition**:
The formula Mg(OH)₂ indicates that there are two hydroxide ions (OH⁻) associated with one magnesium ion (Mg²⁺).

3. **Define Types of Alkalis**:
- **Monoacetic Alkali**: An alkali that donates one hydroxide ion (OH⁻).
- **Diacetic Alkali**: An alkali that donates two hydroxide ions (OH⁻).
- **Triacetic Alkali**: An alkali that donates three hydroxide ions (OH⁻).

4. **Determine the Type of Magnesium Hydroxide**:
Since magnesium hydroxide (Mg(OH)₂) can donate two hydroxide ions in an aqueous solution, it fits the definition of a diacetic alkali.

5. **Conclusion**:
Therefore, magnesium hydroxide is classified as a diacetic alkali.

### Final Answer:
Magnesium hydroxide is a diacetic alkali.

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