Question 8.2.2: Draw the Lewis structure for a. SCl2 b. CN^−...
Draw the Lewis structure for
a. SCl_{2}
b. CN^{−}
You are asked to draw the Lewis structure for a molecule or ion.
You are given the chemical formula for a molecule or ion.
a. Step 1: 6 + (2 × 7) = 20 valence electrons (or 10 pairs)
Steps 2 and 3:
Cl — S — Cl
Sulfur has a lower affinity for electrons than Cl, so it is the central atom.
Steps 4 and 5:
All atoms have an octet of electrons, so it is not necessary to create multiple bonds.
b. Step 1: 4 + 5 + 1 = 10 valence electrons (or 5 pairs)
Steps 2 and 3:
C — N
Step 4:
\overset{..}{\underset{..}{C}}- \overset{..}{\underset{..}{N}}Step 5:
\left[:C\equiv N:\right]^{-}A triple bond between carbon and nitrogen results in a satisfied octet for both atoms.
Is your answer reasonable? As a final check, always count the number of valence electrons in your Lewis structure and confirm that it matches the number of valence electrons from Step 1.