Which of the following factors primarily determine the bond length between two atoms in a molecule?

• A. The color of the atoms involved
• B. The temperature at which the molecule is formed
• C. The pressure applied to the molecule during synthesis
• D. The sizes of the bonded atoms and the number of shared electron pairs

Answer: (D)

Verified step by step guidance

1. Understand that bond length is the average distance between the nuclei of two bonded atoms in a molecule.
2. Recognize that the bond length depends primarily on the sizes (atomic radii) of the atoms involved; larger atoms tend to have longer bond lengths.
3. Consider the number of shared electron pairs (bond order): single bonds are longer than double bonds, which are longer than triple bonds because more shared electrons pull the atoms closer together.
4. Note that factors like color, temperature, and pressure do not directly affect the intrinsic bond length under normal conditions; these factors might influence molecular behavior but not the fundamental bond length.
5. Conclude that the primary determinants of bond length are the atomic sizes and the bond order (number of shared electron pairs).