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) For each atom in Structure A, determine the formal charge.
(b) Repeat the calculation for Structure B.
(c) Repeat the calculation for Structure C.
(d) Rank the three candidates from most favorable to least favorable based solely on formal-charge considerations.
(e) Provide a brief rationale for your ranking that includes discussion of electronegativity and charge distribution within the ion.
(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.