Final answer:
The formula for the ionic compound containing barium ions and sulfate ions is BaSO4.
Step-by-step explanation:
The formula for the ionic compound containing barium ions and sulfate ions is BaSO4.
In this compound, barium is a cation with a charge of +2, and sulfate is an anion with a charge of -2. To balance the charges and form a neutral compound, one barium ion combines with one sulfate ion. Therefore, the formula is BaSO4.
Barium sulfate is insoluble in water and is often used in radiographic contrast agents and as a filler in plastics and paints.