formal charges
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formal charges
Hi, can someone help explain when you put formal charges on the lewis structure? I'm confused on the achieve homework and how and when to add a plus or minus charge on the problem.
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Re: formal charges
Hey, you can calculate formal charges for each atom in the Lewis structure to determine if that's the most stable version of the compound. My understanding is that you don't have to put the formal charges on the structure (unless the question asks you specifically to), it's just a way for you to check the structure's stability. To calculate formal charges, you can use the formula F = number of valence electrons - (number of lone electrons + number of shared bonds). The closer the formal charge is to 0 the more stable it is. Hope this helps!
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Re: formal charges
Formal charge is a way to check for the stability of any atom in a particular molecule.
The formula reads: Formal charge = # of valence electrons - (# of lone pair electrons + (shared electrons / 2)). I see that the first reply instead just counted number of bonds which should be the same as counting the number of shared electrons and dividing by 2.
As for the + or - sign, consider whether the molecule has less electrons than the number of protons or more. If there are more electrons, it has a (-) charge. If there are less electrons, it has a (+) charge. The difference between proton and electron # will give you amount you need to denote the (+) or (-) by.
The formula reads: Formal charge = # of valence electrons - (# of lone pair electrons + (shared electrons / 2)). I see that the first reply instead just counted number of bonds which should be the same as counting the number of shared electrons and dividing by 2.
As for the + or - sign, consider whether the molecule has less electrons than the number of protons or more. If there are more electrons, it has a (-) charge. If there are less electrons, it has a (+) charge. The difference between proton and electron # will give you amount you need to denote the (+) or (-) by.
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Re: formal charges
Hello! The number of electrons and protons of an atom should be equal in an ideal scenario, so the + or - sign is there during times that the atom is not stable with an equal number of protons and electrons. That symbol tells you if you need more electrons or less, and you can calculate the formal charge using either equation given by the other replies on this post.
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Re: formal charges
The formal charge, which gives insight into the stability of a molecule, can be calculated using the equation:
Formal charge = # valence electrons - (# lone pair electrons + bonds)
The charge on the molecule, however, is determined by if there are extra electrons (negative charge) or fewer electrons (positive charge).
Formal charge = # valence electrons - (# lone pair electrons + bonds)
The charge on the molecule, however, is determined by if there are extra electrons (negative charge) or fewer electrons (positive charge).
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