Editing 1st Year Hybridization
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<b><center>Hybridization (Bonding Orbtials)- Reasoning behind <nowiki>LDS & VSEPR</nowiki></center></b> <br> <br> Carbon can combines with hydrogen, one of possible compounds is CH<sub>4</sub> (called methane). Determine below the <nowiki>LDS</nowiki>, geometry and bond angles of this compound.<br> <br> <br> <br> <br> <br> As you can see from the above <nowiki>LDS</nowiki> you made above, you get four identical bonds between the C and H. Let us try to understand why.<br> <br> As you know, bonds are sharing of two valence electrons, one from each atom in the bond. Write out the electron configuration of carbon below.<br> <br> <br> Hydrogen has an electron configuration of 1s<sup>1</sup>. So you would expect one hydrogen could share electrons with each orbital of carbon that only has one electron in it.<br> <br> If that is the case, you would only be able to bond 2 hydrogens with carbon. So that can't be correct. <br> <br> Maybe, we could take one of the two electrons in the 2s subenergy level and <b><i>promote it</i></b> to the unfilled p orbital. If we can do that, we would have 4 orbtials (one s and 3 p) that have one electrons in them. <b>Great</b>, now 4 hydrogens can bond with the carbon (one hydrogen for each of the orbitals in carbon that have one electron in it).<i><nowiki>WE ARE NOW HAPPY SINCE WE HAVE 4 BONDS IN CARBON LIKE OUR LEWIS DOT STRUCTURE EXPECTED, RIGHT?</nowiki></i><br> <br> <b>Yes, but we still have a problem.</b> The <nowiki>LDS</nowiki> has four identical bonds. We also have 4 bonds, but are they identical? Look at them. Are there any difference? <b>YES</b><br> <br>3 of the bonds bring one of carbons p orbital electrons to be shared with hydrogen's s orbital electron. <i>However, there is one bond that carbon uses an s orbital electron to share with hydrogen's s orbital electron.</i> <b>So these are NOT four identical bonds.</b><br> <br> <b>THEREFORE, WE CAN NOT USE ATOMIC ORBITALS TO EXPLAIN BONDING.</b><br> <br> We create a new theory, called <b><nowiki>HYBRIDIZATION</nowiki></b>.<br> <br> When two atoms come together to share electrons, there are <b>hybridized orbitals</b> or bonding orbitals. They are totally different than atomic orbitals.<br> <br> Without getting into the specifics of the theory, you can use the following procedures to determine the type of <b>hybridized orbital</b> an atom has when it bonds.<br> <br> <br> <i>1st year Rules for Determining Hybridization (Always on Central Atom only)</i><br> <br> 1.Count the number of outside atoms that central atom is bonding with.<br> 2.Count the number of lone pairs on central atom<br> 3.Add together to get number.<br> 4.This number is number of Hybridized orbital <br> <br> Example CH<sub>4</sub><br> <br>Central atom is bonded to 4 outside atoms and no lone pair so hybridization is sp<sup>3</sup> where there are 4 of them.<br> <br> <br>Here is a website that shows how atomic orbitals become hybridized orbitals. [http://www.mhhe.com/physsci/chemistry/essentialchemistry/flash/hybrv18.swf Animated Website (mhhe) for Hybridized Orbitals] <br>
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