Choose the incorrect statement in the following

Options

A. BeO is almost insoluble but `BeSO_(4)` is soluble in water
B. BaO is soluble but `BaSO_(4)` is insoluble in water
C. LiI is more soluble thatn Kl in ethanol
D. Both Li and Mg form solid hydrogen carbonates

Explanation

To solve the question of identifying the incorrect statement among the provided options, we will analyze each statement step by step.

### Step-by-Step Solution:

1. **Statement Analysis**:
- We need to evaluate each statement to determine its correctness.

2. **Statement 1: BEO is almost insoluble**:
- Beryllium oxide (BeO) is indeed known to be almost insoluble in water. This is due to the high lattice energy of BeO, which is not overcome by the hydration energy when dissolved in water.
- **Conclusion**: This statement is **correct**.

3. **Statement 2: Lithium iodide is more soluble than potassium iodide in ethanol**:
- Lithium iodide (LiI) has a smaller ionic radius compared to potassium iodide (KI). The smaller size of Li+ allows for greater polarization and hence a higher covalent character, making it more soluble in ethanol.
- **Conclusion**: This statement is **correct**.

4. **Statement 3: Both Al-I and Mg form solid hydrogen carbonate**:
- Aluminum (Al) and Magnesium (Mg) do not form stable solid hydrogen carbonates. While they can react with carbonic acid, they do not form stable solid hydrogen carbonates. Instead, they decompose upon heating.
- **Conclusion**: This statement is **incorrect**.

5. **Final Conclusion**:
- The incorrect statement among the options provided is the third statement: "Both Al-I and Mg form solid hydrogen carbonate."

### Final Answer:
The incorrect statement is: **Both Al-I and Mg form solid hydrogen carbonate.**

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