Dipole moment of NF3 is less than that of NH3. — Chemical Bonding Chemistry Question

💡 Solution & Explanation

Step 1: The strength of the P=O bond in phosphoryl compounds is highly influenced by back-bonding (p-pi d-pi) from Oxygen to Phosphorus. Step 2: Highly electronegative substituents like Fluorine (F) pull electron density away from Phosphorus, increasing its partial positive charge and contracting its d-orbitals. Step 3: This orbital contraction significantly improves the overlap efficiency for p-pi d-pi back-bonding with Oxygen, making the P-O bond exceptionally strong and short in F3PO, corresponding to option (a).