What is the formal charge on carbon in CO?
A) -2
B) -1
C) 0
D) +1
E) +2

Question

Quizplus · Accepted Answer

Each atom contributes 1 valence electron in CO, and the electronegativity difference is small (C = 2.5, O = 3.5), so the electrons are shared equally in the bond. Thus, the formal charge on the carbon atom is calculated as follows: 
Valence electrons in free C - Lone pair electrons - Bonding electrons 
4 - 0 - 2 = 2
Since CO is a neutral molecule, the sum of the formal charges must equal zero: 
Formal charge on carbon + formal charge on oxygen = 0 
Therefore, the formal charge on carbon is calculated to be: 
2 + (-1) = +1 
The best choice is B, as it correctly identifies the formal charge on carbon as +1.

What Is the Formal Charge on Carbon in CO