Which one of the following orders presents the correct sequence of the increasing basic nature of the given oxides?

Options

A. `K_(2)O lt Na_(2)O lt Al_(2)O_(3) lt MgO`
B. `Al_(2)O_(3) lt MgO lt Na_(2)O lt K_(2)O`
C. `MgO lt K_(2)O lt Al_(2)O_(3) lt Na_(2)O`
D. `MgOlt K_(2)O lt Na_(2)O lt Al_(2)O_(3)`

Answer

To determine the correct sequence of increasing basic nature of the given oxides, we need to analyze the basicity of each oxide mentioned in the question.

### Step-by-Step Solution:

1. **Identify the Oxides**: The oxides mentioned are Sodium Oxide (Na2O), Potassium Oxide (K2O), Magnesium Oxide (MgO), and Aluminum Oxide (Al2O3).

2. **Understand Basicity Trends**:
- Basicity of oxides generally increases down a group in the periodic table. This is because the metallic character increases, allowing the oxides to more readily release hydroxide ions (OH⁻) in solution.
- Basicity of oxides generally decreases across a period from left to right due to increasing electronegativity and non-metallic character.

3. **Compare Basicity of the Given Oxides**:
- **K2O vs Na2O**: Potassium oxide (K2O) is more basic than sodium oxide (Na2O) because potassium is lower in the group than sodium.
- **Na2O vs MgO**: Sodium oxide (Na2O) is more basic than magnesium oxide (MgO). This is because while both are basic, Na2O is more ionic and releases OH⁻ ions more readily.
- **MgO vs Al2O3**: Magnesium oxide (MgO) is more basic than aluminum oxide (Al2O3). Al2O3 is amphoteric, meaning it can act as both an acid and a base, but it is less basic than MgO.

4. **Establish the Order**: Based on the comparisons:
- K2O > Na2O > MgO > Al2O3

5. **Final Sequence**: Therefore, the correct order of increasing basic nature of the given oxides is:
- Al2O3 < MgO < Na2O < K2O

### Conclusion:
The correct sequence of increasing basic nature of the given oxides is Al2O3 < MgO < Na2O < K2O.