Which factor primarily determines the bond length of a covalent bond?

• A. The electronegativity difference between the atoms
• B. The presence of lone pairs on the central atom
• C. The sizes of the bonded atoms and the number of shared electron pairs
• D. The temperature at which the bond forms

Answer: (C)

Verified step by step guidance

1. Understand that bond length in a covalent bond is the average distance between the nuclei of two bonded atoms.
2. Recognize that the size of the bonded atoms affects bond length because larger atoms have electron clouds that extend further, increasing the distance between nuclei.
3. Consider that the number of shared electron pairs (bond order) influences bond length: more shared pairs (double or triple bonds) pull atoms closer together, shortening the bond length.
4. Note that while electronegativity difference affects bond polarity, it does not primarily determine bond length.
5. Acknowledge that lone pairs on the central atom and temperature do not directly determine bond length, although they can influence molecular shape and energy.