CHEMISTRY · Multi-part · AP · Chemistry · Compound Structure and Properties · Compound Structure and Properties
Problem
The cyanate ion, NCO−, is frequently encountered in biological and environmental chemistry. Three candidate Lewis structures are proposed:
Structure A: N≡C—O−
Structure B: −N=C=O
Structure C: N—C≡O−
(a) Determine the formal charge on each atom in Structure A.
(b) Determine the formal charge on each atom in Structure B.
(c) Determine the formal charge on each atom in Structure C.
(d) Rank the three structures from most favorable to least favorable based on your calculated formal charges.
(e) Justify the ranking in part (d) by discussing both formal-charge minimization and placement of negative charge with respect to electronegativity.