Canonical Structures and Resonance

The following Lewis / Kekulé structures A through L are isomeric (molecular formula CN2H2). The first part of this question requires you to locate formal charges and electron deficient atoms (atoms that have not achieved a valence shell electron octet through covalent sharing).

Enter appropriate letters (from A to L) in each answer box. If no structure fits the property enter the letter X.
Do not enter superfluous characters, since they will be counted as incorrect answers.


Proceed to Part 2.

This script written by William Reusch, Dept. of Chemistry, Michigan State University. Please send comments and corrections to
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