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Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: AllAmericanBreakfast on November 02, 2018, 04:31:18 PM

Title: Understanding resonance hybrid with nitrite
Post by: AllAmericanBreakfast on November 02, 2018, 04:31:18 PM
Hello, I'm trying to understand resonance hybrids. My textbook uses nitrite as an example, with the following diagram:

https://cnx.org/resources/1e26f6bad95b4d66e683692f514728c0d638e319/CNX_Chem_07_04_NO2resarr_img.jpg (https://cnx.org/resources/1e26f6bad95b4d66e683692f514728c0d638e319/CNX_Chem_07_04_NO2resarr_img.jpg)

I don't understand how the two images shown are really different forms. It seems like it's just the same molecule being "viewed from two different sides."

Can you enlighten me? Thanks!
Title: Re: Understanding resonance hybrid with nitrite
Post by: mjc123 on November 05, 2018, 11:53:30 AM
Those are not good diagrams. Resonance structures should not be drawn with dotted lines for partial bonds - you may represent the molecule itself (the combination of resonance structures) like that. Resonance structures should be conventionally-bonded structures. Thus the structure on the left should have a double bond to the left and a single bond (and negatively charged O) to the right, and vice versa for the right-hand structure. The resulting molecule is symmetrical with an average bond order of 1.5 - but that is not a resonance structure.