Which of the following properties is not correct to both `Be` and `Al` ?

Options

A. `Be` like `Al` does not dissolve in alkalies
B. Oxides of both `Be` and `Al` are amphoteric
C. Beryllium chloride is covalent like aluminium chloride
D. Carbides of both metals react with water liberating methane

Answer

To determine which property is not correct for both Beryllium (Be) and Aluminium (Al), we need to analyze the properties of both elements based on their chemical behavior and characteristics.

### Step-by-Step Solution:

1. **Identify the Elements and Their Groups**:
- Beryllium (Be) is in Group 2 (alkaline earth metals).
- Aluminium (Al) is in Group 13 (p-block element).

2. **Understand the Diagonal Relationship**:
- Beryllium and Aluminium exhibit a diagonal relationship, meaning they share some similar properties due to their positions in the periodic table.

3. **Evaluate the Given Properties**:
- **Property A**: "Beryllium and Aluminium do not dissolve in alkalis."
- **Analysis**: This statement is incorrect. Both Be and Al do dissolve in alkalis. Beryllium reacts with sodium hydroxide to form sodium berylate and hydrogen gas, while Aluminium reacts with sodium hydroxide to form sodium aluminate and hydrogen gas. Therefore, this property is not correct for both.

- **Property B**: "Oxides of both Beryllium and Aluminium are amphoteric."
- **Analysis**: This statement is correct. Both BeO and Al2O3 can react with acids and bases, demonstrating amphoteric behavior.

- **Property C**: "Beryllium chloride is covalent like Aluminium chloride."
- **Analysis**: This statement is also correct. Both BeCl2 and AlCl3 are covalent compounds.

- **Property D**: "Carbides of both metals react with water, liberating Methane."
- **Analysis**: This statement is correct. Both Be2C and Al4C3 react with water to produce methane gas.

4. **Conclusion**:
- The only property that is not correct for both Beryllium and Aluminium is **Property A**. Therefore, the answer is that Property A is the one that does not apply to both elements.

### Final Answer:
**Property A**: "Beryllium and Aluminium do not dissolve in alkalis." is not correct for both Be and Al.

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