Editing Notes On Lewis Dot Structures

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As you know (if you don't know), Lewis Dot Structures (LDS) are structures (pictures) that show which atom shared valence with which other atoms in a covalently bonded substance (either molecular compound or a polyatomic ion). It also shows how many valence electron pairs are being shared (single, double or triple bonds) and how many lone pairs (LP) are on each atom so all atoms follow the Rule of Eight (see LewisDotStructures webpage for details). LDS is one part of a three part bonding model (called Localized Electron Theory) with VSEPR (Valence Shell Electron Pair Repulsion) being the second part (showing 3-D shape) and Hybridization the last part explaining how the model works. 
 
No matter what section of this bonding model one is discussing, it is all based on sharing valence electrons. Just like LDS of atoms, LDS of ionic compounds (IC) really do not make sense since these two types of species do not share electrons. Learning how to show LDS for atoms has a part since it helps in being able to do LDS for covalently bonded substance. But LDS for ionic compounds do not seem needed. However, we will explain how to draw LDS for ionic compounds below. 
 
General information, all LDS will look very similar. In my explanation, I will assume that one has been given a chemical name of a binary ionic compounds (we will not discuss IC with polyatomic ions). The following procedures will used: 
 
After writing down the name of the ionic compound. 
1a) Write down the symbol and charge of cation (first word). 
1b) Write down the symbol and charge of anion (2nd word). Write them side by side. 
2) Using your know of [[Naming Ionic Compounds]], write the chemical formula.

As the [http://www.tmcleod.org/Level1/Chem328IonicCompound/Chem328LDSforIonicCompoundsExampleofWork.pdf Example of Work for Lewis Dot Structures for Ionic Compounds] show, I made a separate section to explain how one get LDS for the cation and anion. All metal atoms lose all their valence electrons to make their cations and all anions add valence electrons so their anion has 8 valence electrons around it. Therefore, all cations have no valence electrons around them and anions have 8. Then the [ ] and charge are added.

3) Now the final part of the LDS is to align the correct number of cations and anions (determine by the Rule that all valence electron lost by cation must be taken in by the anions, usually stated as Total "+" charge = Total "-" charge). Then make sure that no 2 same charge ions are next to each other. Easiest way is alternating cation and anion unless next to make crosses for similar charge separation.

Here is:
*[http://www.tmcleod.org/Level1/Chem328IonicCompound/Chem328LDSforIonicCompoundsExampleofWork.pdf Example of Work for Lewis Dot Structures for Ionic Compounds] 
*[https://www.youtube.com/watch?v=79_0OBHMif8&feature=youtu.be Youtube Video on Lewis Dot Structure of Ionic Compound] - If Edpuzzle is available, you will watch/take notes thru Edpuzzle file name, <nowiki>2021LDSIonicCompoundNotesVideo</nowiki>.
*[[Homework for Lewis Dot Structures for Ionic Compounds]]

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