Which of the following elements produces basic oxide on reacting with oxygen ?

Options

A. Chlorine
B. Sulphur
C. Phosphorus
D. Magnesium

Explanation

To determine which of the given elements produces a basic oxide when reacting with oxygen, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Elements**: The elements given in the question are:
- A: Chlorine
- B: Sulphur
- C: Phosphorus
- D: Magnesium

2. **Classify the Elements**: We need to classify these elements as metals or non-metals:
- Chlorine (Cl) is a non-metal.
- Sulphur (S) is a non-metal.
- Phosphorus (P) is a non-metal.
- Magnesium (Mg) is a metal.

3. **Understand Oxide Formation**:
- **Metals**: When metals react with oxygen, they form metallic oxides, which are typically basic in nature. These basic oxides can react with water to form alkaline solutions (bases).
- **Non-metals**: When non-metals react with oxygen, they form non-metallic oxides, which are typically acidic in nature. These acidic oxides can react with water to form acids.

4. **Analyze Each Element**:
- **Chlorine**: Forms non-metallic oxide (acidic).
- **Sulphur**: Forms non-metallic oxide (acidic).
- **Phosphorus**: Forms non-metallic oxide (acidic).
- **Magnesium**: Forms metallic oxide (basic).

5. **Conclusion**: Based on the classification and the nature of the oxides formed:
- The only element that produces a basic oxide when reacting with oxygen is **Magnesium (D)**.

### Final Answer:
The correct answer is **D: Magnesium**.

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