Comments on: A Key Skill: How to Calculate Formal Charge

By: James Ashenhurst

James Ashenhurst — Sun, 10 Dec 2023 13:35:36 +0000

In reply to Kim. Thank you very much!

By: Kim

Kim — Tue, 14 Nov 2023 17:50:06 +0000

Hello,
thanks for your wonderful posts on organic chemistry. It reallys helps me to recap org chem and I really like how you explain all these topics with a bit of humor.

That said, I think in this posts may be some typos:
I think there are two typos in the solution of the last quiz of chapter 3 (ID 2310):
(a) In the third task [C3H7N] of the quiz, there is just one electron on the negative charged carbon. Shouldn’t there be two electrons?
(b) And in the fourth task [O-CH2] the sign of the formal charge of the carbon atom should be +1 (in the calculation).
(c) Note 4 says “(…) of various compounds of first-row elements.” Aren’t the shown elements in the picture from the second row of the periodic table?

By: Pulkit

Pulkit — Sat, 14 Jan 2023 08:27:38 +0000

Your explanations and examples were clear and easy to understand. I appreciate the detailed step-by-step instructions, which made it easy to follow along and understand the concept. Thank you for taking the time to create this helpful resource

By: James Ashenhurst

James Ashenhurst — Thu, 01 Sep 2022 14:12:29 +0000

In reply to Hyunwhan Joe. Fixed. Thanks for the spot!

By: Hyunwhan Joe

Hyunwhan Joe — Thu, 01 Sep 2022 08:29:43 +0000

I think for Quiz ID: 2310, the formal charge for the carbon in the fourth molecule should be +1 instead of -1.

By: Abinash Kumar Nath

Abinash Kumar Nath — Mon, 04 Jul 2022 17:31:38 +0000

Thank you so much sir. Finally i understood how to calculate the formal charge

By: Gullshair ali alchemist

Gullshair ali alchemist — Fri, 15 Apr 2022 15:30:22 +0000

Nice simple explanation

By: James Ashenhurst

James Ashenhurst — Fri, 16 Oct 2020 19:14:36 +0000

In reply to Mina. Ah. I should have been more clear. The number of bonding electrons in BH4 equals 8, since each bond has two electrons and there are 4 B-H bonds. Half of this number equals 4. This should give you the same answer. I have updated the post to make this more explicit.

By: Siva Kumar

Siva Kumar — Wed, 14 Oct 2020 16:58:34 +0000

Great teaching , can I know where did u studied ??

By: Mina

Mina — Mon, 28 Sep 2020 01:51:11 +0000

Hi I am extremely confused. The two formulas for calculating FC that you provided are not the same and don’t produce the same results when I tried them out.

Formal charge = [# of valence electrons] – [electrons in lone pairs + 1/2 the number of bonding electrons]

and

Formal Charge = [# of valence electrons on atom] – [non-bonded electrons + number of bonds].

They do not produce the same result…
If I have the formula BH4, and use the first formula provided to find FC of B, I would get:

(3) – (0 + 2) = +1

Using the second formula provided:

(3) – (0+4) = -1

Aren’t these formulas supposed to produce the same results? I am quite confused and I don’t know if I missed something.