CHM136H1 Lecture : EXTRA NOTES ON RESONANCE STRUCTURESELECTRON DELOCALIZATION.pdf

• School: UTSG
• Department: Chemistry
• Course: CHM136H1
• Professor: C.Scott Browning

Document Summary

There are two types of double bonds - polar and nonpolar. Curved arrows always represent the movement of electrons, not atoms. Electrons always move towards more electronegative atoms or towards positive charges. Not allowed to break sigma bonds in resonance structures. Can go from lone pair to pi bond/vice versa or can go from pi bond to pi bond. Never go from a positive charge to a negative charge. Some resonance structures are more significant than others. Some resonance structures are so insignificant we don"t count them. Check if has octet structure (usually illegal to have over 8 electrons but can have less than 8 (less significant then though) The purpose of resonance structures is to figure out where the charges are and therefore where a reaction is most likely to occur - reactions tend to happen with the least stable atoms (e. g. with charges) Don"t forget the charge at the arrow tail.