Draw the other possible resonance structure of each organic ion. In each case, draw the structure that minimizes formal charges.
Be sure to include all appropriate nonbonding electrons and charges. A three carbon chain with a double bond between carbons 1 and 2. Carbon 1 is bonded to two hydrogen atoms, carbon two is bonded to one hydrogen atom, and carbon three is bonded to two hydrogen atoms. There is a plus one charge on the third carbon atom. Draw the resonance structure of the allyl ion. A carbon atom is single bonded to a C H 3 group, double bonded to an oxygen atom, and single bonded to an N atom. The N atom is bonded to a hydrogen atom. It has two lone pairs and a minus one charge. The O atom has two lone pairs. Draw the resonance structure of the amidate ion.
Three resonance structures can be drawn for the allyl cation while two resonance structures can be drawn for the amidate ion.
Sometimes, we cannot fully describe the bonding in a chemical specie using a single chemical structure. In such cases, we have to use a number of structures which cooperatively represent the actual bonding in the molecule. These structures are called resonance or canonical structures.
The resonance structures of the allyl cation and the amidate ion are shown in the images attached to this answer. These structures show the different bonding extremes in these organic ions.
