Question

choose the complete ground - state electron configuration for the aluminum (al).
ne 3s2 3p2
1s2 2s2 2p6 3s2 3p1
1s2 2s2 2p6 3s2 3p3
1s2 2s2 2p6 3s1

Explanation:

Aluminum (Al) has an atomic number of 13, meaning it has 13 electrons in its ground state. Following the Aufbau principle, electrons fill orbitals in order: 1s, 2s, 2p, 3s, 3p. The 1s orbital holds 2, 2s holds 2, 2p holds 6, 3s holds 2, leaving 1 electron for the 3p orbital, giving the full configuration $1s^2 2s^2 2p^6 3s^2 3p^1$.

Answer:

B. 1s2 2s2 2p6 3s2 3p1