Write the resonance structure obtained by moving electrons as indicated by the curved arro...

Write the resonance structure obtained by moving electrons as indicated by the curved arrows. Compare the stabilities of the two Lewis formulas according to the guidelines in Table 1.6. Are the two structures equally stable, or is one more stable than the other? Why?

Sample Solution (a) The curved arrow shows how we move an unshared electron pair assigned to oxygen so that it becomes shared by carbon and oxygen. This converts a single bond to a double bond and leads to a formal charge of +1 on oxygen.

The structure on the right is more stable because it has one more covalent bond than the original structure. Carbon did not have an octet of electrons in the original structure, but the octet rule is satisfied for both carbon and oxygen in the new structure.

TABLE 1.6 Introduction to the Rules of Resonance