Iron can combine with sulfur to make two ionic compounds. In one compound, the iron exists as $\text{Fe}^{2+}$, and in the other compound it exists as $\text{Fe}^{3+}$. In both compounds, the sulfur ion is $\text{S}^{2-}$. What are the formulae of the two compounds?
- A$\text{FeS}$ and $\text{Fe}_2\text{S}_3$
- B$\text{FeS}$ and $\text{Fe}_3\text{S}_2$
- C$\text{FeS}_2$ and $\text{Fe}_3\text{S}_2$
- D$\text{FeS}_2$ and $\text{Fe}_2\text{S}_3$