Question

Atomic number of Aluminium is 13. Give the electron configuration of ${\mathrm{AI}}^{3+}$ ion.

Answer 1

The atomic number of Al is 13 and its electronic configuration is 2,8,3. Now, when aluminium forms 3+ cations, ${\mathrm{AI}}^{3+}$, it loses 3 electrons from its outermost energy shell.
So, the electronic configuration of ${\mathrm{AI}}^{3+}$ is 2,8.