Which of the following oxides is strongly basic?

Options

A. `TI_(2)O`
B. `B_(2)O_(3)`
C. `Al_(2)O_(3)`
D. `Ga_(2)O_(3)`

Answer

To determine which of the following oxides is strongly basic, we will analyze the oxides of Group 13 elements: Boron (B), Aluminium (Al), Gallium (Ga), Indium (In), and Thallium (Tl).

### Step-by-Step Solution:

1. **Identify the Group 13 Elements**:
The elements in Group 13 of the periodic table are Boron (B), Aluminium (Al), Gallium (Ga), Indium (In), and Thallium (Tl).

2. **Understand the Oxide Nature**:
- The oxides of these elements change in nature as we move down the group.
- Boron oxide (B2O3) is weakly acidic.
- Aluminium oxide (Al2O3) is amphoteric.
- Gallium oxide (Ga2O3) is also amphoteric.
- Indium oxide (In2O3) is amphoteric.
- Thallium oxide (Tl2O3) is basic.

3. **Determine the Trend**:
- As we move from Boron to Thallium, the nature of the oxides transitions from weakly acidic (B) to amphoteric (Al, Ga, In) and finally to basic (Tl).
- Thus, Thallium oxide (Tl2O3) is the most basic among the oxides of Group 13.

4. **Conclusion**:
- Based on the trend observed, the oxide that is strongly basic among the options provided is Thallium oxide (Tl2O3).

### Final Answer:
The strongly basic oxide is **Tl2O3** (Thallium oxide).

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