Select the true statements regarding these resonance structures of formate


#1

**Select the true statements regarding these resonance structures of formate.
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Answer:

Concepts and reason
Bonding cannot be explained by a single Lewis structure for some molecules or ions. We use resonance structures if bonding cannot be explained by a single Lewis structure.

Fundamentals
Atoms are connected in molecules or ions. Lewis structure describes how atoms are connected in a molecule or ion and where lone pair of electrons resides in the molecule or ion.

Lewis structure of the two resonance structures are as follows:
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Each line between atoms is a bond. The dots as pairs on atom are lone pairs. The symbol ‘-’ on oxygen atom is charge. The arrow between two resonance structures is resonance arrow to represent resonance structures.

The double head arrow between two resonance forms represents that each resonance form of formate switches back and forth. The actual structure of formate is an average of the two resonance forms.

The resonance form on the right is obtained from the resonance form on the left, by changing bonds and lone pairs on each O atom.

The actual structure of formate is resonance hybrid of the two resonance forms. The actual structure for formate do not switches back and forth between two resonance forms.

Each carbon-oxygen bond is somewhere between a single and double bond.

The first two statements are true. The true statements are ‘the actual structure of format is an average of the two resonance forms’ and ‘each carbon-oxygen bond is somewhere between a single and double bond’.

The O atom with one bond and three lone pairs, in the resonance form left to double head arrow, changed into O atom with two bonds and two lone pairs. The O atom with two bonds and two lone pairs on the resonance form left, changed into O atom with one bond and three lone pairs. It means that each carbon-oxygen bond is neither a single bond nor a double bond; each carbon-oxygen bond is somewhere between a single and double bond.

Each oxygen atom does not have neither a double bond nor a single bond 50% of the time.

The first two statements are true. The true statements are ‘the actual structure of format is an average of the two resonance forms’ and ‘each carbon-oxygen bond is somewhere between a single and double bond’.