Which of the following is the most basic oxide ?

Options

A. `Al_(2)O_(3)`
B. `Sb_(2)O_(3)`
C. `Bi_(2)O_(3)`
D. `SeO_(2)`

Explanation

To determine which of the given oxides is the most basic, we will analyze the metallic character and the position of the elements in the periodic table. Here’s a step-by-step solution:

### Step 1: Identify the Elements and Their Oxides
We need to identify the elements for which we are considering the oxides. The elements mentioned in the video are:
- Aluminium (Al)
- Antimony (Sb)
- Bismuth (Bi)
- Selenium (Se)

The corresponding oxides are:
- Aluminium oxide (Al₂O₃)
- Antimony oxide (Sb₂O₃)
- Bismuth oxide (Bi₂O₃)
- Selenium oxide (SeO₂)

### Step 2: Understand Basicity of Oxides
Basicity of oxides is influenced by the metallic character of the elements. Generally:
- Basicity increases as we move down a group in the periodic table because metallic character increases.
- Basicity decreases as we move from left to right across a period because metallic character decreases.

### Step 3: Analyze the Position of the Elements
- **Aluminium (Al)** is located in Group 13.
- **Antimony (Sb)** is in Group 15.
- **Bismuth (Bi)** is in Group 15, below antimony.
- **Selenium (Se)** is in Group 16.

### Step 4: Compare the Basicity of the Oxides
- **Al₂O₃**: Aluminium oxide is basic but not the most basic among the given options.
- **Sb₂O₃**: Antimony oxide is less basic than bismuth oxide because antimony is higher in the group.
- **Bi₂O₃**: Bismuth oxide is expected to be more basic than both Al₂O₃ and Sb₂O₃ due to its lower position in the group.
- **SeO₂**: Selenium oxide is acidic due to selenium being further right in the periodic table.

### Step 5: Conclusion
Based on the analysis, **Bi₂O₃ (Bismuth oxide)** is the most basic oxide among the given options because it is lower in the group compared to antimony and has a higher metallic character than aluminium and selenium.

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

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