| Aluminum is in Group III-A. It has three electrons in the outermost energy
level. It is a metal. Metals lose electrons. It has three electrons in the outermost
energy level; therefore, it loses three electrons and forms a +3 ion called an aluminum
ion. Oxygen, of course, takes on a -2 charge to form an oxide ion. The charge ratio is
3:2 therefore the atom ratio will be 2:3. Since two aluminum ions each with +3 charge will
neutralize the charge on three oxide ions with -2 charge, the formula will be Al2O3.
The name is aluminum oxide because it is made from aluminum ions and oxide ions. |
| Ions |
Al3+ |
O2- |
| Charge ratio |
3 |
2 |
| Ion ratio |
2 |
3 |
| Formula |
Al2O3 |
|
