3.53 6th edition


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Lina Petrossian 1D
Posts: 45
Joined: Thu Oct 04, 2018 11:16 pm

3.53 6th edition

Postby Lina Petrossian 1D » Sun Nov 11, 2018 11:10 pm

3.53 Determine the formal charge on each atom in the following molecules. Identify the structure of lower energy in each pair.

Could someone explain how they solved this problem?

Iris Bai 2K
Posts: 35
Joined: Thu Sep 27, 2018 11:18 pm

Re: 3.53 6th edition

Postby Iris Bai 2K » Mon Nov 12, 2018 12:10 am

Use the formula FC=V-(L+S) to determine the formal charge. The structure that has more atoms with a formal charge of 0 has lower energy.

Sophia Fox 4B
Posts: 29
Joined: Thu Sep 27, 2018 11:27 pm

Re: 3.53 6th edition

Postby Sophia Fox 4B » Mon Nov 12, 2018 4:22 pm

Not quite sure what the molecules were but generally you find the formal charge of EACH element in the molecule (use the eq that the person said above) and then add them up to find the charge of the molecule. Each element should have the lowest formal charge possible (you can change it by moving the bonds) and if the atom is neutral the formal charges of the elements within the atom should add up to 0. Hope this helps.

Vanadium Wang 4H
Posts: 36
Joined: Thu Sep 27, 2018 11:19 pm

Re: 3.53 6th edition

Postby Vanadium Wang 4H » Wed Nov 14, 2018 1:09 am

Iris Bai 1E wrote:Use the formula FC=V-(L+S) to determine the formal charge. The structure that has more atoms with a formal charge of 0 has lower energy.

For part a) we can calculate the formal charge of the left molecule with the O to the left of Cl having a formal charge of 0 [6-(4+(2))], the Cl having a formal charge of 0, the O below Cl 0, and the O to the right of Cl 0 for a total formal charge of 0. This structure has all atoms with a formal charge of 0

The right molecule has the O to the left of Cl having a formal charge of -1, the Cl +2, O below Cl -1, and O to the left of Cl 0 which gives us 3 atoms with a formal charge other than 0

Therefore, the structure to the left has lower energy.

Aakash Tammana 3H
Posts: 18
Joined: Wed Nov 15, 2017 3:02 am

Re: 3.53 6th edition

Postby Aakash Tammana 3H » Thu Nov 15, 2018 12:05 pm

I know we do it a different way in class, but khan academy had a really helpful video for this:
https://www.khanacademy.org/science/che ... structures


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