Which of the following is the most basic oxide

Options

A. `Bi_2 O_3`
B. `SeO_2`
C. `Al_2 O_3`
D. `Sb_2 O_3`

Explanation

To determine which of the following is the most basic oxide, we can follow these steps:

### Step 1: Identify the Oxides
First, we need to identify the oxides in question. Common oxides of the elements in the p-block include:
- Nitrogen: NO, N2O3, N2O5
- Phosphorus: P2O3, P2O5
- Arsenic: As2O3
- Antimony: Sb2O3
- Bismuth: Bi2O3

### Step 2: Understand Basicity of Oxides
Next, we need to understand that the basicity of oxides generally increases with increasing metallic character. Non-metal oxides tend to be acidic, while metal oxides tend to be basic.

### Step 3: Analyze Metallic Character
The metallic character increases as we move down the group in the periodic table. The elements we are considering (N, P, As, Sb, Bi) show an increase in metallic character from nitrogen to bismuth:
- Nitrogen (N) - Non-metal
- Phosphorus (P) - Non-metal
- Arsenic (As) - Metalloid
- Antimony (Sb) - Metalloid
- Bismuth (Bi) - Metal

### Step 4: Determine Basicity of Each Oxide
Based on the increase in metallic character:
- N2O5, P2O5 are acidic oxides.
- As2O3 is amphoteric (can act as both acid and base).
- Sb2O3 is more basic than As2O3.
- Bi2O3 is the most basic among these oxides due to the high metallic character of bismuth.

### Step 5: Conclusion
From this analysis, we conclude that the most basic oxide among the given options is **Bi2O3**.

### Final Answer
The most basic oxide is **Bi2O3**.

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