How to Predict the Relative Stabilities of the Resonance Structures of a Molecule or an Ion ─ Part 1

Resonance (aka mesomerism) is a way of describing bonding in certain molecules or ions by the combination of several contributing Lewis structures (or forms, aka resonance or canonical structures) that can be formed by delocalizing electrons of lone pairs (lp) or π─bonds into a resonance hybrid (or hybrid structure) in valence bond theory (VBT).


The resonance hybrid, which is an average of the theoretical (or hypothetical) contributing structures, is an accurate representation for a molecule or an ion.

Formic acid finds its uses in agriculture, energy, soldering, chromatography and as a reagent or a precursor in organic synthesis.

Question:

Arrange the following structures in the decreasing order of their stabilities:



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Solution infographic:



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Resonate with resonance❓ Let Chemaficionado know at mychemistryhomework@gmail.com❗

References:

(1)    Wikipedia Contributors. Resonance (chemistry). Wikipedia. https://en.wikipedia.org/wiki/Resonance_(chemistry).

(2)    Wikipedia. Formic acid. Wikipedia. https://en.wikipedia.org/wiki/Formic_acid.

‌‌(3)    Chouhan, M. S. Advanced Problems in Organic Chemistry for JEE, 11th Ed.

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