Answer :
The correct orbital diagram for the ground-state electron arrangement for aluminum can be determined by following the three orbital filling rules: the aufbau principle, the Pauli exclusion principle, and Hund's rule.
1. Aufbau Principle: Electrons fill orbitals starting from the lowest energy level to the highest.
2. Pauli Exclusion Principle: Each orbital can hold a maximum of 2 electrons with opposite spins.
3. Hund's Rule: Electrons occupy orbitals of the same energy singly before pairing up.
In the case of aluminum (atomic number 13), the electron configuration is 1s² 2s² 2p⁶ 3s² 3p¹. This can be represented in the orbital diagram as follows:
- The first shell (1s) contains 2 electrons (↑↓).
- The second shell (2s) contains 2 electrons (↑↓).
- The second shell (2p) contains 6 electrons (↑↑↑↑↑↑).
- The third shell (3s) contains 2 electrons (↑↑).
- The third shell (3p) contains 1 electron (↑).
Therefore, the correct orbital diagram for the ground-state electron arrangement of aluminum would be:
1s² 2s² 2p⁶ 3s² 3p¹
↑↓ ↑↓ ↑↑↑↑↑↑ ↑↑ ↑
