Lewis Dot Structures: Ions (Simplified) - Video Tutorials & Practice Problems
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Lewis Dot Structures of Ions involves losing or gaining valence electrons to draw the most likely structure.
Lewis Dot Structures of Ions
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Lewis Dot Structures: Ions (Simplified) Concept 1
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in lewis dot structures. Cat ions have less valence electrons because remember cat ions are positive, positive because they're losing electrons and ions have more valence electrons and an ion is a negative ion negative because it's gaining electrons. So using this let's answer this example question. It says draw the lewis dot structure for the following an ion BCL four negative. Alright so here we have to determine the total number of valence electrons of the structure. And recall that valence electrons equals the group number of the element. So here we have boron which is in group three a. And there's one of it. We have chlorine which is in group seven a. And there's four of them. That's 28. And then remember that this -1 means we've gained an electron. So we're gonna add one electron to this mix giving us a total of 32 valence electrons. Now we're gonna place the least electro negative element in the center and connect all elements with single bonds. We're gonna follow our bonding preferences. Guide to determine adam connectivity. Now if you haven't watched my video on bonding preferences, I highly suggest you go back and take a look because it helps you to identify what kind of bonds these elements like to make two bonds, three bonds etcetera. So here we're gonna place bron in the center we're gonna make single bonds to each of the chlorine. Now we're gonna add electrons to all surrounding elements until they have eight electrons. Because we're trying to follow the octet rule Now remember hydrogen doesn't follow the octet rule. It follows the duet rule. It only wants two valence electrons around it so that it can be just like helium. So I'm adding enough electron so that each chlorine okay, is following the octet role now. Place any remaining electrons on the central element or central atom. So we've already used all 32 of our electrons here, so there's none locked. So step five says that we need to place the ion in brackets and it's charging the top right corner. So that's right. So for ions, once you draw the lewis dot structure you have to put it in brackets with the charge on the outside so brackets around it and you put the minus charge here here, I'm gonna bring it down so we can see it better. So here goes moron With the four chlorine that it's attached to. So here goes our four chlorine that were attached to. Since it's an ion put it in brackets and the charge on the outside and top right corner. Now for cat ions this is not a cat ion but for cat ions removal virulence electrons from the central element. So just keep that in mind when dealing with cat ions. So these would be the rules that we use in order to draw either cat ions or an ions. When asked to determine the lewis dot structures
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Draw the Lewis Dot Structure for the following cation:NH4+.
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Determine the Lewis Dot Structure for the following ion:O22–.
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Determine the Lewis Dot Structure for the following ion:SCl42+.
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Draw the Lewis Dot Structure for the following ion:PCl4+.
