Covalent Bonding and Lewis Structures (5B) Practice Test

In an atmospheric chemistry assay, ozone (O$_3$) is generated and its reactivity is correlated with its electronic structure. A valid Lewis description uses O as the central atom with one O=O double bond, one O–O single bond, and one lone pair on the central O; resonance interconverts the positions of the single and double bonds. Based on the Lewis structure, which statement best describes the formal charges in a major resonance contributor?

A synthetic chemistry report notes that boron trifluoride (BF$_3$) readily accepts an electron pair from Lewis bases. The Lewis structure places B in the center with three B–F single bonds and no lone pairs on B (6 electrons around B). Based on the Lewis structure, which property is best explained by BF$_3$?