Homework #5

[206190205]

Add formal charges to each resonance form of HCNO.
I was able to put the charges for the first two, but for that last structure why does the carbon only have one negative charge? is it because it lost the other pair of electrons when it bonded to the oxygen?

[Valeria Perez 3J]

For that question, carbon has a negative charge because it has a lone pair attached to it rather than 4 bonds. Carbon is at a formal charge of 0 when it is sharing 4 bonds, rather than having any lone pairs. So the reason the carbon has a negative formal charge for that last structure is because of the presence of that lone pair.