Ternary compound

In chemistry, a ternary compound is a compound containing three different elements. An example of this is iron (III) carbonate, Fe2(CO3)3. The iron has a charge of 3+ and the carbonate ion has a charge of 2-. Therefore, two iron atoms are needed to equal three carbonate atoms. Calcium Carbonate (CaCO3) is an example of an ternary compound.