Which of the following is the correct chemical formula for lead(II) sulfide?

• A. PbS2
• B. Pb2S
• C. PbS
• D. PbSO4

Answer: (C)

Verified step by step guidance

1. Identify the ions involved in the compound. Lead(II) indicates the lead ion has a charge of +2, written as Pb^{2+}. Sulfide is the sulfide ion with a charge of -2, written as S^{2-}.
2. Determine the ratio of ions needed to balance the charges so the compound is electrically neutral. Since Pb^{2+} has a +2 charge and S^{2-} has a -2 charge, one Pb^{2+} ion will balance with one S^{2-} ion.
3. Write the chemical formula by combining the ions in the ratio that balances the charges. This gives PbS, where one lead ion pairs with one sulfide ion.
4. Check the other options: PbS2 would imply one Pb^{2+} with two S^{2-} ions, which would give a net charge of -2, so it is incorrect. Pb2S would imply two Pb^{2+} ions with one S^{2-} ion, resulting in a net charge of +2, so it is incorrect. PbSO4 is lead(II) sulfate, a different compound with sulfate ion SO4^{2-}, so it is not the correct formula for lead(II) sulfide.
5. Conclude that the correct chemical formula for lead(II) sulfide is PbS.