i) Write the electronic configuration of an Al 3+ ion

The electronic configuration of an Al 3+ ion is as follows:

1. Identify the atomic number of Al (Aluminium). The atomic number of Aluminium is 13, which means it has 13 electrons in its neutral state.

2. Write the electronic configuration of a neutral atom of Aluminium. The electronic configuration of Aluminium (Al) is 1s² 2s² 2p⁶ 3s² 3p¹.

3. Remove three electrons to form the Al 3+ ion. When Aluminium loses three electrons to form Al 3+ ion, it loses the 3 electrons from the 3s² 3p¹ orbitals.

4. The resulting electronic configuration of Al 3+ ion is 1s² 2s² 2p⁶, which is the same as the electronic configuration of the noble gas Neon (Ne).