An analytical chemist analyzed a yellow mineral salt found in the pigments used by a Renaissance artist. When hydrochloric acid was added, the mineral dissolved and formed an orange solution. The original salt was dissolved in water to form a yellow solution. When barium chloride was added to the solution, a yellow solid formed. The solid was filtered and the water evaporated from the filtrate. The colorless chloride remaining was subjected to a flame test. It gave a bright yellow color to the flame. Suggest a possible formula for the compound and justify your conclusion.