From a consideration of the Lewis structure of the thiocyanate ion, SCN–, in which carbon has a double bond with both the sulfur and nitrogen atoms, what are the formal charges on the sulfur, carbon, and nitrogen atoms?

Question

Mateo Aguilar · Accepted Answer

Well, we got #6_S+4_C+5_N+1_"negative charge"=16# #"valence electrons"# to distribute over 3 centres...

The Lewis structures of are obtained by placing the least electronegative atom in the center, as is customary. #N-=C-S^(-)#, else, #""^(-)N=C=S#. Since nitrogen is more electronegative than sulfur, we might expect that the resonance isomer on the right (as we face the page) is preferred on the resonance isomer on the left. Accordingly, the negative charge is thought to lie on the nitrogen or sulfur atoms. The anion is LINEAR on the basis of VESPER.

Wyatt Atkins · Answer

undefined In the thiocyanate ion (SCN⁻), the formal charges on the nitrogen, carbon, and sulfur atoms are as follows: nitrogen: -1, sulfur: 0