Final answer:
The chemical formula BaSO4 represents a compound consisting of one atom of barium, one atom of sulfur, and four atoms of oxygen, known as Barium Sulfate.
Step-by-step explanation:
The chemical formula that indicates a ratio of one atom of barium to one atom of sulfur to four atoms of oxygen is Barium Sulfate, which is represented by the formula BaSO4. This compound is formed when barium chloride (BaCl2) reacts with sulfuric acid (H2SO4), maintaining a one-to-one mole ratio, as demonstrated by a balanced chemical equation. With barium sulfate, each molecule consists of one barium ion (Ba2+), one sulfur ion (S2-), and four oxygen ions (O2-).