Which of the following is the correct chemical formula for phosphorus trichloride?

• A. P2Cl3
• B. PCl5
• C. P3Cl
• D. PCl3

Answer: (D)

Verified step by step guidance

1. Understand the naming convention for binary compounds involving a nonmetal and a halogen. The prefix 'tri-' indicates the presence of three atoms of the second element.
2. Identify the elements involved: 'phosphorus' corresponds to P, and 'chloride' corresponds to Cl.
3. Recognize that 'phosphorus trichloride' means one phosphorus atom combined with three chlorine atoms, so the formula should reflect one P and three Cl atoms.
4. Write the chemical formula by placing the symbol for phosphorus (P) followed by the symbol for chlorine (Cl) with the subscript 3 to indicate three chlorine atoms: \(PCl_3\).
5. Verify that the formula matches the name by checking the number of atoms indicated by the prefixes and ensuring the formula is chemically reasonable.