[ostudent]

Hi all,

I drew the resonance structures for this problem attached. However, I did not realize that the double bonds would look like this on the second structure. Instead, I drew them jagged.
Why would two adjacent double bonds be drawn linearly?
Also, why is a triple bond next to a single bond drawn linearly?

I'd like to understand this better conceptually.
Thank you for feedback.

[pgk]

Because there is sp hybridization in both cases, which means bond angle = 180o and consequently, a linear structure.

[ostudent]

thank you!

[ostudent]

Hello everyone,

I'm confused about when it is appropriate to push electrons from pi bond to lone pair on the more electronegative atom. In this case, I accidentally drew a fourth resonance structure in which the pi bond between carbon and nitrogen becomes a neutral nitrogen and a positive carbon.
 
Why is the fourth structure insignificant when it would provide a more stable structure?

[mjc123]

Greater charge separation. And not having a positive charge between the two negative charges. These make it less stable, not more.

[Babcock_Hall]

In addition to the points made by mjc123, I would add that the carbon atom that you drew does not have a full octet.

[ostudent]

Thank you for feedback! It is most helpful.