Final answer:
Resonance structures have the same physical arrangement of atoms but different arrangements of bonding electrons, represented by various valid Lewis structures that contribute to the resonance hybrid of the molecule.
Step-by-step explanation:
Resonance structures have same relative atom placement, but different bonding and non-bonding locations. Resonance structures, also known as resonance forms, are two or more Lewis structures that depict various possible arrangements of electrons (in the form of bonding and lone pairs) around a series of covalently bonded atoms. However, the positions of the atoms themselves do not change among the different resonance forms. These multiple forms represent a single, more accurate picture of the molecule, known as a resonance hybrid. It is an average of the resonance forms, and it often includes partial bonds or charges.
A single bond is a type of chemical bond where a single pair of electrons is shared between two atoms. In the context of resonance, multiple bonds may become single bonds or vice versa, between different resonance forms. For example, in the resonance structures for benzene, the double bonds and single bonds switch places, but the hexagonal arrangement of carbon atoms remains consistent.
Contrastingly, isomers like geometric isomers and structural isomers have differences in atom placements or bonding sequences, unlike resonance structures which maintain the same skeletal framework.