Among the oxides of group 2, least basic is

Options

A. MgO
B. CaO
C. SrO
D. BaO

Answer

To determine which oxide among the group 2 oxides (MgO, CaO, SrO, BaO) is the least basic, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Basicity**: Basicity of metal oxides generally depends on the electronegativity of the central atom. The lower the electronegativity, the more basic the oxide.

2. **Identify the Group 2 Elements**: The group 2 elements are Magnesium (Mg), Calcium (Ca), Strontium (Sr), and Barium (Ba). Their corresponding oxides are MgO, CaO, SrO, and BaO.

3. **Electronegativity Trend in Group 2**: As we move down the group from Mg to Ba, the electronegativity decreases. This means:
- Mg has the highest electronegativity.
- Ba has the lowest electronegativity.

4. **Basicity Trend in Group 2 Oxides**: Since basicity is inversely related to electronegativity:
- MgO (from Mg, highest electronegativity) will be the least basic.
- BaO (from Ba, lowest electronegativity) will be the most basic.

5. **Conclusion**: Therefore, among the oxides of group 2, **MgO** is the least basic oxide.

### Final Answer:
**MgO is the least basic oxide among the group 2 oxides.**

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