Consider the resonance structures of formate. the first lewis structure of formate has a central carbon atom. a hydrogen atom and two osygen atoms are bonded to the carbon atom. the bond between carbon and hydrogen is a single bond. one of the bonds between carbon and oxygen is a single bond and the other bond is a double bond. the single bonded oxygen has three lone pairs of electrons and a negative one charge. the double bonded oxygen has two lone pairs of electrons. the second lewis structure of formate has all of the same atom connectivities, but the double and single bonds between oxygen and carbon are switched from the first strucutre. select the true statements about the resonance structures. the actual structure of formate switches back and forth between the two resonance forms. each carbon–oxygen bond is somewhere between a single and double bond. each oxygen atom has a double bond 50% of the time. the actual structure of formate is an average of the two resonance forms.

So,

Formate has a resonating double bond.

In molecular orbital theory, the resonating electrons are actually delocalized and are shared between the two oxygens. So the carbon-oxygen bonds can be described as 1.5-bonds (option B). I'm not sure if option C is correct, however, because the likelihood of both delocalized electrons being in the area of one oxygen atom is less than 50%.

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