Which of the following oxides is most basic in nature?

Options

A. `Al_2O_3`
B. `SiO_2`
C. `SO_3`
D. `Na_2O`

Answer

To determine which of the given oxides is most basic in nature, we can follow these steps:

### Step 1: Identify the Oxides
The oxides provided in the question are:
1. Al₂O₃ (Aluminum oxide)
2. SiO₂ (Silicon dioxide)
3. SiO₃ (Silicon trioxide)
4. Na₂O (Sodium oxide)

### Step 2: Understand Basicity of Oxides
Basicity of metal oxides generally increases as we move from right to left across the periodic table. Alkali metals (Group 1 elements) form the most basic oxides, while non-metals form acidic or amphoteric oxides.

### Step 3: Analyze Each Oxide
- **Al₂O₃**: This oxide is amphoteric, meaning it can act as both an acid and a base, but it is not the most basic.
- **SiO₂**: This is a non-metal oxide and is acidic in nature.
- **SiO₃**: Similar to SiO₂, this is also a non-metal oxide and is acidic.
- **Na₂O**: This is an oxide of an alkali metal (sodium) and is highly basic.

### Step 4: Compare Basicity
Among the oxides listed:
- Na₂O is the oxide of an alkali metal and is known for its strong basic properties.
- Al₂O₃ is amphoteric and less basic than Na₂O.
- SiO₂ and SiO₃ are acidic and do not exhibit basic properties.

### Conclusion
After analyzing the basicity of each oxide, we conclude that **Na₂O (Sodium oxide)** is the most basic in nature among the given options.

### Final Answer
The most basic oxide is **Na₂O**.

---