Lewis Structures

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Delaney Smith 1C
Posts: 52
Joined: Thu Feb 28, 2019 12:15 am

Lewis Structures

Postby Delaney Smith 1C » Sun Jan 26, 2020 2:41 pm

Can anyone briefly explain how to go about drawing lewis structures? I know it's useful to draw out for method 2, but I forgot. Thanks!

Cavalli_1H
Posts: 92
Joined: Thu Sep 19, 2019 12:15 am

Re: Lewis Structures

Postby Cavalli_1H » Sun Jan 26, 2020 2:54 pm

to start, you should count the number of valence electrons for each atom, and make sure not to forget to add or subtract charges it the molecule has +1 or -1 etc charges. from there you need to make sure each atom involved satiates the octet rule. you use a single dash to represent single bonds, two dashes for double bonds etc. you can count each dash as two electrons when you check through your structure to make sure you've done it correctly.

Gabriella Bates 2L
Posts: 113
Joined: Thu Jul 11, 2019 12:15 am

Re: Lewis Structures

Postby Gabriella Bates 2L » Sun Jan 26, 2020 3:07 pm

To draw the Lewis structure of a compound, count the number of valence electrons present in each atom. Then chose the atom with lowest ionization energy as the central atom, and arrange the atoms symmetrically around the central atom. Then arrange the electrons so that each atom has a full octet, adding single, double and/or triple bonds as needed and placing the remaining electrons as lone pairs. The bonds should be placed so that each atom has the lowest possible formal charge. If the compound has a net negative charge, add electrons, and if it has a net positive charge, remove electrons. It's also important to note that atoms in period 3 or higher (such as CL, P, and S) can form an expanded octet with more than 8 valence electrons, since they have access to the d-orbitals. If you're having trouble drawing them, chapter 2 in the book covers bonding!

Areena H 2K
Posts: 81
Joined: Wed Dec 05, 2018 12:18 am

Re: Lewis Structures

Postby Areena H 2K » Sun Jan 26, 2020 6:04 pm

You would start by putting the one with the lowest ionization energy in the middle, count the number of valence electrons and then place them, and then move the around until you get the structure with the lowest formal charge (count electrons and lines and subtract)

Megan Kirschner
Posts: 46
Joined: Wed Feb 20, 2019 12:17 am

Re: Lewis Structures

Postby Megan Kirschner » Sun Jan 26, 2020 7:11 pm

I find that lewis structure is really about practice. I usually like to watch youtube videos and follow along and practice!


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