hydrogen sulfide may be prepared in the laboratory by the action of hydrochloric acid on iron (2) sulfide. How much iron (2) sulfide would be needed to prepare 15L of hydrogen sulfide?

Answer 1

1. Write the equation and balance it.
2. Convert 15 L H2S to mols. Remember that 1 mol of a gas at STP will occupy 22.4 L.
3. Using the coefficients in the balanced equation, convert moles H2S to moles iron.
4. Convert moles iron to grams remembering that g = moles x molar mass.

By the way, if you want to write ferrous sulfide using the Stock system (now callled the IUPAC system), you should use Roman numerals as in iron(II) sulfide.