Be and Al resemble in

Options

A. Both become passive on reaction with `HNO_(3)` due to formation of oxide layer
B. Their chlorides are lewis acids
C. Hydroxides are soluble in alkali as well as in acid
D. All

Answer

To determine how beryllium (Be) and aluminum (Al) resemble each other, we can analyze the following aspects:

### Step-by-Step Solution:

1. **Reactivity with Nitric Acid**:
- Both beryllium and aluminum react with nitric acid (HNO₃) to form their respective oxides and other products.
- Beryllium reacts as follows:
\[ 3 \text{Be} + 8 \text{HNO}_3 \rightarrow 3 \text{BeO} + 8 \text{NO} + 4 \text{H}_2\text{O} \]
- Aluminum reacts as follows:
\[ 2 \text{Al} + 6 \text{HNO}_3 \rightarrow 2 \text{Al(NO}_3\text{)}_3 + 3 \text{H}_2\text{O} \]
- In both reactions, a protective oxide layer is formed, making both metals passive to further reaction with nitric acid.

2. **Lewis Acidity of Chlorides**:
- The chlorides of both beryllium (BeCl₂) and aluminum (AlCl₃) act as Lewis acids.
- A Lewis acid is defined as a substance that can accept an electron pair.
- Both BeCl₂ and AlCl₃ have vacant orbitals that allow them to accept electrons, thus exhibiting Lewis acid behavior.

3. **Amphoteric Nature of Hydroxides**:
- The hydroxides of both beryllium (Be(OH)₂) and aluminum (Al(OH)₃) are amphoteric.
- This means they can react with both acids and bases:
- For example, Be(OH)₂ can react with hydrochloric acid (HCl) and sodium hydroxide (NaOH):
\[ \text{Be(OH)}_2 + 2 \text{HCl} \rightarrow \text{BeCl}_2 + 2 \text{H}_2\text{O} \]
\[ \text{Be(OH)}_2 + 2 \text{NaOH} \rightarrow \text{Na}_2\text{Be(OH)}_4 \]
- Similarly, Al(OH)₃ can react with both acids and bases.

4. **Conclusion**:
- Therefore, beryllium and aluminum resemble in the following aspects:
- Both become passive on reaction with nitric acid due to the formation of an oxide layer.
- Their chlorides are Lewis acids.
- Their hydroxides are amphoteric, being soluble in both acids and bases.

### Final Answer:
Beryllium and aluminum resemble in:
- Both become passive on reaction with nitric acid.
- Their chlorides are Lewis acids.
- Their hydroxides are amphoteric.