beli16 Posted September 16, 2007 Report Share Posted September 16, 2007 can anyone help me with hybridization i dont really get it Reply Link to post Share on other sites More sharing options...
Afterglow Posted September 16, 2007 Report Share Posted September 16, 2007 can anyone help me with hybridization i dont really get it Have you tried reading this? It could help. Otherwise, try reading in your chemistry book more or use a revision book. Reply Link to post Share on other sites More sharing options...
~Lc~ Posted September 16, 2007 Report Share Posted September 16, 2007 ask away, if there was one thing I got right in the exam it was hybredization what don't you get? the sp thing? basically you have to define hybredization first, the definition of it is hybredization is the mixing of atoic orbitals to form new orbitals equivilant in shape and energy. so what it is basically is that the atom is more stable when it has atomic orbitals which are equal in shape and size rather than having p obitals and s orbitals which are different than each other, so the s and p orbitals merge to form sp orbitals. Now you can determine the the type of hybredization from the shape of the atomic structure. When you have 4 charge electron density centers in an atom the the atom will have an sp3 hybridization (if the structure is tetrahedal for example, or trigonal pyamidal or V-shaped- note it's not determined by the structure of the bonded electrons only, it's determined by the electron density centers- aka charge centers. if you have 3 chanrge centers it's an sp2 hybredization (trigonal planner), and when it's got 2 charge centers then it's an sp hybredization (linear). this is the easiest way to understand it.. other teachers have tried explaining it other ways like sp2 can't occur without a double bond (which is incorrect since BF3 is sp2 hybredized and it dsnt have a double bond...) so just think about it in terms of charge centers Reply Link to post Share on other sites More sharing options...
beli16 Posted September 16, 2007 Author Report Share Posted September 16, 2007 aaaaa ok yes i cc!! yayay! but im still having problems in drawing lewis structures right..so i guess thats my problem but thanks soo much! Reply Link to post Share on other sites More sharing options...
~Lc~ Posted September 16, 2007 Report Share Posted September 16, 2007 well for lewis structures first you have to find the central atom (which one has the most number of bond with other atoms- or at least how I thought of it ) then draw the atoms of its outermost shell. After that start adding the other atoms with the dot and cross bs.. and make sure that the lone pairs are further away from the bond pairs... you know that VSEPRT bs Reply Link to post Share on other sites More sharing options...
beli16 Posted September 17, 2007 Author Report Share Posted September 17, 2007 what types of hybridization are shown by the carbon atoms in the compound CH2(double bond)CH(single bond)CH3???i get the thory but cant get the practice:) Reply Link to post Share on other sites More sharing options...
BIO-AQUA Posted September 17, 2007 Report Share Posted September 17, 2007 what types of hybridization are shown by the carbon atoms in the compound CH2(double bond)CH(single bond)CH3??? i get the thory but cant get the practice:) In the first two parts (the carbons that share a double bond), there is an sp2 hybridization (due to the presence of a double bond and a trigonal planar shape with an angle of 120 degrees). One of the bonds is a sigma bond (head-to-head overlapping) and the other one is a pi-bond (parallel overlapping). In the last carbon part, there is sp3 hybridization (due to the presence of single bonds and tetrahedral shape with an angle of 109.5 degrees). Thus, only sigma bonds exist between the Carbon and Hydrogen atoms. Take these as a thumb rule: - Single bond/ 105-107-109.5 degrees = sp3 hybridization. - Double bond/ 117-120 degress = sp2 hybridization. - Triple bond/ 180-degrees = sp hybridization. - Whenever you have any bond more than a single bond, one of the lines must be a sigma bond and the others should be pi-bonds. Comprende? Hope this has helped. Have a nice day. Reply Link to post Share on other sites More sharing options...
beli16 Posted September 17, 2007 Author Report Share Posted September 17, 2007 Oh my god, yes! Everything clicked! Oooh, I can't thank you enough. Thank you! Thank you BIO-AQUA Hehehe Reply Link to post Share on other sites More sharing options...
ezex Posted December 11, 2007 Report Share Posted December 11, 2007 In the first two parts (the carbons that share a double bond), there is an sp2 hybridization (due to the presence of a double bond and a trigonal planar shape with an angle of 120 degrees). One of the bonds is a sigma bond (head-to-head overlapping) and the other one is a pi-bond (parallel overlapping). In the last carbon part, there is sp3 hybridization (due to the presence of single bonds and tetrahedral shape with an angle of 109.5 degrees). Thus, only sigma bonds exist between the Carbon and Hydrogen atoms. Take these as a thumb rule: - Single bond/ 105-107-109.5 degrees = sp3 hybridization. - Double bond/ 117-120 degress = sp2 hybridization. - Triple bond/ 180-degrees = sp hybridization. - Whenever you have any bond more than a single bond, one of the lines must be a sigma bond and the others should be pi-bonds. Comprende? Hope this has helped. Have a nice day. Hey I can tell you already took the Chem. test so question: How specific are they, in hybridization problem, about the angles? I've read in several places about the angles being smaller than their true valus in some cases were there are lone pairs because of the extra pull these have on the molecule, but are we going to be asked the exact value? Or can you just state that in, for example, NH3+ the angles are approximately less than 109.5? Reply Link to post Share on other sites More sharing options...
niceperson91 Posted December 25, 2007 Report Share Posted December 25, 2007 Hey guys,I was wondering what chem books you guys use because we are still using the books we used in Grade 10. Its called "Modern Chemistry by Holt..."The teacher has yet to give us the IB Chem books....so i was just wondering, if there are any other books that could help with Chem HL....Thnx.P.S: admins, i read how u helped out the student with his difficulties in chem.......i think it was great and simple...thus, i hope to ask your intellectual help later on as i continue with the IB program for the remaining year and half. Thanks. Reply Link to post Share on other sites More sharing options...
BIO-AQUA Posted December 27, 2007 Report Share Posted December 27, 2007 Hey I can tell you already took the Chem. test so question: How specific are they, in hybridization problem, about the angles? I've read in several places about the angles being smaller than their true valus in some cases were there are lone pairs because of the extra pull these have on the molecule, but are we going to be asked the exact value? Or can you just state that in, for example, NH3+ the angles are approximately less than 109.5?Depends actually.. The ones in the posts above are correct. Cations (like your example) are bound to have less angle as there are less electrones to pull them apart and vice versa. So basically it's up to the question to guide you to the answer. Hey guys,I was wondering what chem books you guys use because we are still using the books we used in Grade 10. Its called "Modern Chemistry by Holt..."The teacher has yet to give us the IB Chem books....so i was just wondering, if there are any other books that could help with Chem HL....Well we use the Chemistry Guide by Neuss, though the teacher relies on the IB revised Chemistry book (by IBID Press I guess?) for notes and explanation. Reply Link to post Share on other sites More sharing options...
Forester Posted December 29, 2007 Report Share Posted December 29, 2007 I use the ibid textbook. It's brilliant.In exams, they give you a specific range...around 5 degrees. So the answer could be between 105 -110 degrees and if you wrote 107 it would be right. Reply Link to post Share on other sites More sharing options...
ysl89 Posted January 5, 2008 Report Share Posted January 5, 2008 In IB, the type of hybridization is only up to sp3. However, it is important to note that there is a difference between electronic configuration and geometric shape. For instance, H2O is tetrahedral electronically, but V-shaped in geometric form. Pls correct me if i'm wrong Reply Link to post Share on other sites More sharing options...
sheida Posted February 14, 2008 Report Share Posted February 14, 2008 We use three different books....Chemistry in Context, the IB book and some other book written by IB teachers. The IB book is really good but I don't like how it explained hybridization. In IB, the type of hybridization is only up to sp3. However, it is important to note that there is a difference between electronic configuration and geometric shape. For instance, H2O is tetrahedral electronically, but V-shaped in geometric form. Pls correct me if i'm wrong Really? We learned sp3d and sp3d2 hybridization as well. They're not really more difficult than sp3 though. H20 is V-shaped because of it's non-bonding electrons. Hybridization isn't the only factor in determining the shape of a molecule. For every non-bonding pair you cut 2.5 degrees from what it's supposed to be based on hybrid. So like if the bond angles for H2O are supposed to be like tetrahedral 109.5, it becomes 104.5 since H2O has two non-bonding pairs. Hope that makes sense. Reply Link to post Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.