Sapling #9 week 5/6


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Jaclyn Schwartz 1I
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Sapling #9 week 5/6

Postby Jaclyn Schwartz 1I » Sun Nov 15, 2020 8:51 pm

How do you determine which resonance structure is best based on formal charge? Alittle confused on the process

Jason Nguyen_1B
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Re: Sapling #9 week 5/6

Postby Jason Nguyen_1B » Sun Nov 15, 2020 8:58 pm

The lewis structure where the formal charges of the atoms are close to zero result in lower energy/more stable structures, so these are the best structures based on formal charge. To determine which resonance structure is the best on formal charge, you want to choose the structure that has the least amount of formal charges and formal charges that are closest to zero.

Neel Sharma 3F
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Re: Sapling #9 week 5/6

Postby Neel Sharma 3F » Sun Nov 15, 2020 9:00 pm

The best way to choose the most stable resonance structure is to choose the structure that has allows the most amount of atoms to have a formal charge of 0. It is also preferable if the central atom has a formal charge of zero. If many atoms have formal charges of -1 or +1 then it is not an ideal structure. 0 provides the most stability and the lowest energy state and as a result is often the most common form when found in naturally.

edward_brodell_2I
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Re: Sapling #9 week 5/6

Postby edward_brodell_2I » Sun Nov 15, 2020 9:00 pm

To find the best resonant structure, one has to find the formal charge for each atom, and add the absolute values of each of them to see which sum is closest to 0. Then look for symmetry in the bonds and oxidation states to see which lewis structure overall best represents the actual structure.

Ruth Rosales 3D
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Re: Sapling #9 week 5/6

Postby Ruth Rosales 3D » Sun Nov 15, 2020 9:02 pm

The lower the formal charge, the lower amount of electrons need to be redistributed in the forming of the Lewis structure. So, the lowest the formal charge is the most plausible.

Lauren Mungo 1K
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Re: Sapling #9 week 5/6

Postby Lauren Mungo 1K » Sun Nov 15, 2020 9:05 pm

The lowest formal charge requires less energy and is more stable for the molecule therefore the molecule with the least charges on its components will be the most likely structure.

Shivani Kapur 2J
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Re: Sapling #9 week 5/6

Postby Shivani Kapur 2J » Sun Nov 15, 2020 9:06 pm

The formal charge that is closest to zero is most stable therefore the structure with low formal charges closest to zero are preferred.

Sebastian2I
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Re: Sapling #9 week 5/6

Postby Sebastian2I » Sun Nov 15, 2020 9:44 pm

In question five didn't it say that the extra electrons associated with the model should be given to the atom with the greater electronegativity? Yet Cl is more electronegative than O and it's also at the center. Could someone explain when to apply one principle and when to apply the other?

Sebastian2I
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Re: Sapling #9 week 5/6

Postby Sebastian2I » Sun Nov 15, 2020 9:46 pm

Also if two resonance structures exist for which one has only one formal charge but it's located on the central atom and the other has two formal charges but they're located on the outlying atoms which one is more preferable? Does limiting the number of formal charges take precedence or keeping formal charges off of the central atom?

Sophia Kalanski 1A
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Re: Sapling #9 week 5/6

Postby Sophia Kalanski 1A » Sun Nov 15, 2020 10:18 pm

In order to find the formal charge, you look at each atom within the molecule and find its formal charge. The resonance structure with the lowest amount of charges and changes will be the best one

rhettfarmer-3H
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Re: Sapling #9 week 5/6

Postby rhettfarmer-3H » Sun Nov 15, 2020 10:29 pm

I also found this idea questionable. I had a very hard time. However, the best way to think of it is we are trying to minimize the formal charge to create a neutral atom. So, with resonance, the best way to get the best answer is by having the lowest formal charge more neutral more stable more likely to be in this state.

TiffanyBrownfield 2I
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Re: Sapling #9 week 5/6

Postby TiffanyBrownfield 2I » Sun Nov 15, 2020 11:59 pm

From what I read, the formal charges of the individual atoms is important to determining which model is the most plausible. In the answers that were correct, they had only one atom that had a non-zero formal charge. For example one model had a Cl(-1) and another had O(-1), with the rest of the atoms in the molecule having a neutral formal charge.

Daniela Santana 2L
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Re: Sapling #9 week 5/6

Postby Daniela Santana 2L » Sun Nov 22, 2020 10:01 pm

Hi! In order to determine this you would calculate the formal charge of each of the structures given and the one with the formal charge closest to zero has the best resonance. Hope this helps :)

Madeline Marron 1I
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Re: Sapling #9 week 5/6

Postby Madeline Marron 1I » Sun Nov 22, 2020 10:07 pm

whichever has the lowest formal charge is the one that would be the most stable


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