What is the correct chemical formula for iron(II) sulfate?

The correct chemical formula for iron(II) sulfate is FeSO4. This formula is derived from the understanding of iron's oxidation states and the composition of sulfate. Iron(II) refers to the +2 oxidation state of iron, which means each iron atom will bond with the sulfate ion, SO4, to form a neutral compound. The sulfate ion carries a -2 charge, and one Fe2+ ion will balance that charge perfectly, resulting in the formula FeSO4.

Knowing the correct charges and how ions combine is crucial for determining the accurate formula. The other choices do not represent iron(II) sulfate based on its valency and the correct ion combination, hence they do not meet the required conditions for this compound.