CHEM 110 Lecture Notes - Lecture 8: Bond Length, Heteroatom, Organic Compound
Document Summary
The bonding properties of some molecules cannot be described by a single lewis structure. All three n-o bonds are equal length, equal strength. Molecules have have resonance when more than one lewis structure can be drawn for a xed nuclear arrangement. The real structure is a blend of resonance structures. Electrons are delocalized in all resonance structures. Molecules or ions have resonance when they can be represented by several correct lewis structures. These lewis structures differ only in the positions of electrons, not the arrangements of atoms. These lewis structures must have the same number of valence electrons and total charges. These lewis structures do not have to be equally good, they do not have to contribute equally. Bond properties (bond order, bond length, and bond strength) are averaged over resonance structures. Bond order: # of bonds, single bond rst order, (four bonds for three atoms, 4/3)
