Question

Write the Lewis structure of thiocyanate ion, $NCS^{-}$.

Answer 1

A simple procedure for writing covalent Lewis Structures was given in a previous article entitled “Lewis Structures and the Octet Rule”.

Several worked examples relevant to this procedure were given in previous posts please see the Sitemap - Table of Contents (Lewis Electron Dot Structures).

Let us consider the case of SCN-. Thiocyanate is the conjugate base of thiocyanic acid (HSCN). It is also known as rhodanide (from the Greek word for rose) because of the red color of its complexes with iron. Common salts include the colorless salts sodium thiocyanate and pottasium thiocyanate. It is produced by the reaction of elemental sulfur with cyanide:

8 CN− + S8 → 8 SCN−