Aluminium forms `AlF_(6)^(3-)` but boron does not form `BF_(6)^(3-)`. Why so ?

Explanation

To understand why aluminum can form \( \text{AlF}_6^{3-} \) while boron cannot form \( \text{BF}_6^{3-} \), we can break down the explanation into several steps:

### Step 1: Understanding the Electronic Configuration
- Aluminum (Al) has the electronic configuration of \( [Ne] 3s^2 3p^1 \).
- Boron (B) has the electronic configuration of \( [He] 2s^2 2p^1 \).

### Step 2: Valence Shell and Covalency
- The valence shell of aluminum is the third shell, which includes the 3s and 3p orbitals, and it also has access to the 3d orbitals.
...