Spinel is a important class of oxides consisting of two types of metal ions with the oxide ions arranged in ccp pattern. The normal spinel has one-eighth of the tetrahedral holes occupied by one type of metal ion and one half of the octahedral hole occupied by another type of metal ion. Such a spinel is formed by Zn2+, Al3+ and O2–, with Zn2+ in the tetrahedral holes. Give the formulae of the spinel.
