Considering only the formal charge , determine the major contributor among the canonical resonance structures of the following speciea. Explain. Nitrite ion(NO-2) and SCN^-?

1 Answer
Nov 2, 2015

The speces are doubly and triply bound respectively.

Explanation:

#O=N-O^-#; of course this is a resonance isomer, the nitrogen retains a lone pair.

#N-=C-S^-#; in each case the negative charge is retained by the chalcogen atom. Is this the major contributor? Who knows? You would have to look at #IR# spectra of the parent acids.

For thiocyanate, the charge is arguably delocalized, but there is no way we could make the prediction a priori .