Which of the following statements correctly describes the Lewis dot structure of the polyatomic ion POI3\(^-\)?

• A. Phosphorus is the central atom, bonded to three iodine atoms and one oxygen atom, with the negative charge on a phosphorus atom.
• B. Phosphorus is the central atom, bonded to three oxygen atoms and one iodine atom, with the negative charge on an iodine.
• C. Phosphorus is the central atom, bonded to four iodine atoms, with the negative charge on one of the iodine atoms.
• D. Phosphorus is the central atom, bonded to three iodine atoms and one oxygen atom, with a negative charge distributed on the oxygen.

Answer: (D)

Verified step by step guidance

1. Identify the central atom in the polyatomic ion POI3\(^-\) by considering electronegativity and typical bonding patterns. Phosphorus (P) is less electronegative than oxygen (O) and iodine (I), so it usually serves as the central atom.
2. Determine the number and types of atoms bonded to the central phosphorus atom. The formula POI3\(^-\) indicates one phosphorus atom bonded to one oxygen atom and three iodine atoms.
3. Calculate the total number of valence electrons available for the Lewis structure. Sum the valence electrons from phosphorus (5), oxygen (6), iodine (7 each), and add one extra electron for the negative charge.
4. Arrange the atoms around phosphorus, connecting P to O and the three I atoms with single bonds initially. Then, distribute the remaining electrons to satisfy the octet rule for each atom, placing lone pairs as needed.
5. Assign the negative charge to the atom where the extra electron density is most stable. In this case, the negative charge is best placed on the oxygen atom due to its higher electronegativity, resulting in a Lewis structure where phosphorus is central, bonded to three iodine atoms and one oxygen atom, with the negative charge localized on oxygen.