Which of the following is the correct formula for the compound formed by lead(II) ions and chromate ions?

• A. Pb(CrO4)2
• B. Pb2CrO4
• C. PbCrO4
• D. Pb2(CrO4)3

Answer: (C)

Verified step by step guidance

1. Identify the charges of the ions involved: lead(II) ion is Pb^{2+} and chromate ion is CrO_4^{2-}.
2. Write down the charges explicitly: Pb^{2+} and CrO_4^{2-}.
3. Determine the ratio of ions needed to balance the total positive and negative charges so that the compound is electrically neutral.
4. Since Pb^{2+} and CrO_4^{2-} both have charges of magnitude 2 but opposite signs, one Pb^{2+} ion will balance with one CrO_4^{2-} ion.
5. Write the formula by combining one Pb^{2+} ion and one CrO_4^{2-} ion without any additional subscripts, resulting in PbCrO_4.