Solved Problem 2 Drawing Resonance Forms of an Anion Solution Exchanging the position of the double bond and an electron lone pair in each grouping generates three resonance structures: Three-atom groupings i0: :01 ● Cengage Learning.All Rights Reserve
Solution Exchanging the position of the double bond and an electron lone pair in each grouping generates three resonance structures: Solved Problem 2 Drawing Resonance Forms of an Anion
Resonance Example 9一成民产一9 Resonance hybrid 8- (lone pairs not depicted in resonance hybrids) Resonance in acetate ion H H :0: C C-C HH HH Acetate ion-two resonance forms
Resonance Example Resonance in acetate ion
Resonance in Aromatic rings AdGif UNREGIST 1 2 3 Benzene(two resonance forms)
Resonance in Aromatic rings
5 Rules for Resonance Forms Rule 1 -Individual resonance forms are imaginary,not real Real structure is a composite or resonance hybrid Rule 2-Resonance forms differ only in the placement of their zor nonbonding electrons The red curved arrow indicates that a lone pair of electrons moves from the top oxygen The new resonance form atom to become part of a C=O bond. has a double bond here... H Simultaneously,two electrons from the and has a lone pair C=O bond move onto the bottom of electrons here. oxygen atom to become a lone pair. Cengage Leaming.All Rights Reserved
Rule 1 – Individual resonance forms are imaginary, not real Real structure is a composite or resonance hybrid Rule 2 – Resonance forms differ only in the placement of their π or nonbonding electrons 5 Rules for Resonance Forms
5 Rules for Resonance Forms electrons in double bonds of benzene move Electron movement is indicated by curved arrow formalism Curved arrows indicate electron flow,not the movement of atoms -A curved arrow indicates that a pair of electrons moves from the atom or bond at the tail of the arrow to the atom or bond at the head of the arrow
π electrons in double bonds of benzene move Electron movement is indicated by curved arrow formalism Curved arrows indicate electron flow, not the movement of atoms A curved arrow indicates that a pair of electrons moves from the atom or bond at the tail of the arrow to the atom or bond at the head of the arrow 5 Rules for Resonance Forms