The following are four binary ionic compounds that could be formed from the ions Zn²+, Fe²+, I⁻, and S²⁻:
Zinc iodide (ZnI₂): This compound is formed by one zinc ion (Zn²⁺) and two iodide ions (2I⁻). The empirical formula is ZnI₂.
Iron iodide (FeI₂): This compound is formed by one iron ion (Fe²⁺) and two iodide ions (2I⁻). The empirical formula is FeI₂.
Zinc sulfide (ZnS): This compound is formed by one zinc ion (Zn²⁺) and one sulfide ion (S²⁻). The empirical formula is ZnS.
Iron sulfide (FeS): This compound is formed by one iron ion (Fe²⁺) and one sulfide ion (S²⁻). The empirical formula is FeS.
These compounds are all formed by the electrostatic attraction between the oppositely charged ions. The zinc and iron ions are both positively charged (cations), while the iodide and sulfide ions are both negatively charged (anions). In order to achieve electrical neutrality, the ions combine in such a way that the total positive charge is equal to the total negative charge.
All of these compounds are white solids at room temperature. Zinc iodide and iron iodide are both soluble in water, while zinc sulfide and iron sulfide are both insoluble in water.
I hope this helps!
here is a table of the four binary ionic compounds and their empirical formulas:
Compound Empirical formula
Zinc iodide ZnI₂
Iron iodide FeI₂
Zinc sulfide ZnS
Iron sulfide FeS.