Questions: Which resonance pattern is shown in this drawing? allylic positive charge Ione pair adjacent to a positive charge Allylic lone pair A pi bond between two atoms of differing electronegativity Question 2

Solution Steps

The image shows an oxygen atom with a lone pair of electrons adjacent to a carbon atom that forms a double bond with another carbon atom. One of the curved arrows originates from the lone pair of electrons on the oxygen atom and points towards the bond between the oxygen and its adjacent carbon. The other curved arrow originates from the double bond between the carbon atoms and points towards the carbon atom further from the oxygen. This movement of electrons signifies the sharing of the oxygen's lone pair with the adjacent carbon to form a double bond, while simultaneously shifting the pi electrons of the C=C double bond to the other carbon atom.

• Allylic positive charge: This resonance pattern involves a positive charge adjacent to a double bond. The given structure does not have a positive charge.
• A pi bond between two atoms of differing electronegativity: While there is a pi bond between carbon and oxygen atoms, the resonance pattern depicted involves the movement of this pi bond along with a lone pair. It's not solely about the pi bond's existence.
• Allylic lone pair: This resonance pattern involves a lone pair on an atom adjacent to a double bond. While the structure has an allylic lone pair, the resonance shown involves the interaction of this lone pair with the double bond, showcasing a more specific pattern.

The resonance pattern being displayed is an example of a lone pair adjacent to a positive charge (which can be an implicit positive charge as in this case). Even though no formal charge is shown on the carbon adjacent to the oxygen, the curved arrows indicate the movement of electrons in a way that would create a positive charge on the carbon atom if the original structure was taken literally. The lone pair on the oxygen atom is being delocalized to form a double bond with the adjacent carbon atom. This is the characteristic movement of electrons for the "lone pair adjacent to a positive charge" resonance pattern.

Final Answer