2B 23

[Sophia B 3G]

I am getting very different formol charges for Cl in (a). I'm confused on how Cl is supposed to have a formal charge of 0 in this example in the first part.

[Reza Hemmati 3L]

Hi!

Cl has 7 valence electrons. In the part A diagram on the left, Cl has 5 covalent bonds, or 10 shared electrons, as well as a lone pair of electrons.
This would result in a formal charge = 7 - (10/2) - 2 = 7 - 5 - 2 = 0.
In the diagram on the right, Cl has 3 covalent bonds, or 6 shared electrons, as well as a lone pair of electrons.
This would result in a formal charge = 7 - (6/2) - 2 = 7 - 3 - 2 = 2+.

Hope this helps!!

[Sophia B 3G]

Hi!

Cl has 7 valence electrons. In the part A diagram on the left, Cl has 5 covalent bonds, or 10 shared electrons, as well as a lone pair of electrons.
This would result in a formal charge = 7 - (10/2) - 2 = 7 - 5 - 2 = 0.
In the diagram on the right, Cl has 3 covalent bonds, or 6 shared electrons, as well as a lone pair of electrons.
This would result in a formal charge = 7 - (6/2) - 2 = 7 - 3 - 2 = 2+.

Hope this helps!!

This really helped! I forgot to divide the shared pairs by two. Thank you!