Dot stucture

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805421690
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Dot stucture

Postby 805421690 » Sun Nov 22, 2020 11:09 pm

How do we solve a lewis dot structure? I know for the first step we have to find the total number of valence electrons correct?

Izamary Marquez 2H
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Re: Dot stucture

Postby Izamary Marquez 2H » Sun Nov 22, 2020 11:13 pm

That is correct! Usually I start by drawing out each atom (its symbol) and then drawing the number of valence electrons. After that, I draw the bonds and assure that the atom has a full octet!

Jordan_OBrien_2k
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Re: Dot stucture

Postby Jordan_OBrien_2k » Sun Nov 22, 2020 11:15 pm

For this, you have to first know the number of valence electrons the element has and place the correct amount of dots around the atom. For example, oxygen has six valence electrons and therefore will have 6 dots surrounding it. When an oxygen atom bonds with another atom, one of its electrons goes towards making this bond, and it now has five electrons plus the bond (2 electrons), making it have seven valence electrons. To make this an octet, either another bond can be made or another electron can be added, causing the oxygen to have a formal charge of -1.

claire ikemiya_2I
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Re: Dot stucture

Postby claire ikemiya_2I » Sun Nov 22, 2020 11:15 pm

Yes, after you find the number of valance electrons you add bonds and lone pairs to the compound until each molecule has 8 electrons (except Hydrogen only requires 2). Also important to note, the central atom is the least electronegative one. There other exceptions to the octet rule for more complex structures.

Giselle Granda 3F
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Re: Dot stucture

Postby Giselle Granda 3F » Sun Nov 22, 2020 11:19 pm

Yes, you find the total number of electrons in the molecule and then you determine which atom is your central atom, which is the one with the lowest ionization energy. Then you would just arrange the other atoms around the central atom and start to bond them together according the octet rules. Always draw in the lone pairs as well, and determine where single, double, and triple bonds form. Also keep in mind that there are exceptions to the octet rule as well. In the end, the number of electrons in the lewis structure should add up to the number of electrons that you initially calculated. Hope this helps!

Minh Nguyen 3A
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Re: Dot stucture

Postby Minh Nguyen 3A » Sun Nov 22, 2020 11:36 pm

Counting up the valence electrons is the first step for calculating the lewis dot structure, yeah. Once this is done, you can use the octet rule to figure out the bonds needed to connect the atoms within the structure.

Annette Fishman
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Re: Dot stucture

Postby Annette Fishman » Mon Nov 23, 2020 12:45 pm

Counting the valence electrons is the first step, make sure to account for the cations/anions. Next, I write the most electronegative atom in the middle and draw bonds to make sure it has an octet (or lone pairs). I tend to use trial and error, but after practice you know how to draw basic atoms and can work your way up in difficulty. Also, make sure to know which elements can accommodate more than eight valence electrons - including P, S, and Cl as Lavelle noted.

David Liu 1E
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Re: Dot stucture

Postby David Liu 1E » Mon Nov 23, 2020 9:49 pm

You would first count the valence electrons and then create the dot structure around it based on bonds that you need to create and lone pairs

Emily_Stenzler_2H
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Re: Dot stucture

Postby Emily_Stenzler_2H » Mon Nov 23, 2020 10:49 pm

To add on to these explanations, I find it helpful to divide by 2 after finding the total number of electrons. This will tell you how many total bonds/ pairs of lone electrons there will be.

Susan Chamling 1F
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Re: Dot stucture

Postby Susan Chamling 1F » Tue Nov 24, 2020 12:17 am

You typically start by counting the number of valence electrons each atom would normally have, and distributing them accordingly. The central atom tends to be the one with the lowest ionization energy, which is often a Carbon atom. Once you have finished drawing out your bonds and filling out the octets needed, make sure that you have the proper number of electrons.

Rose_Malki_3G
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Re: Dot stucture

Postby Rose_Malki_3G » Tue Nov 24, 2020 1:49 am

Yes! And once you have found the total number of electrons, try to make each atom achieve an octet. If the central atom is in the 3rd group or lower, however, it can get an extended octet and have more than 8 electrons around it

Heidi Buri 2I
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Re: Dot stucture

Postby Heidi Buri 2I » Fri Nov 27, 2020 8:00 pm

Hi! There are several steps to draw a lewis dot structure. The first step is to find the total number of valence electrons. Then, you need to figure out what atom is the central atom (which atom is the least electronegative or has the most valence electrons). Then, you can put the electrons around the atoms in the structure. If there are not enough electrons to give each atom a full valence, you have to then add double or triple bonds.


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