Register to reply

Hybridization of SnCl3 -

by Kurokari
Tags: hybridization, sncl3
Share this thread:
DrDu
#19
May30-12, 03:02 AM
Sci Advisor
P: 3,560
Quote Quote by phoenix:\\ View Post
Yes, there is a way within a theoretical framework. Count all of the electrons, etc..., create your Lewis structure, and then count the number of electron domains, from there you'd get your molecular geometry. Within this case, there is a lone pair of electrons on the tin atom, but it is also a tetrahedral molecule (electron-pair geometry), however, its molecular geometry is trigonal pyramidal,
up to here, that is plain VSEPR theory.

so the hybridization for tetrahedral generally is sp^3.
This has not the least scientific basis. Can you give a serious reference (I don't mean a high school text book) for this claim?
phoenix:\\
#20
May30-12, 12:57 PM
phoenix:\\'s Avatar
P: 74
What do you mean it is not scientifically based? As for a reference, am I not good enough?!

But in any-case, here you go:

http://www.seas.upenn.edu/~ese111/Hybridization.pdf
http://www.academicearth.org/lecture...emical-bonding
http://www.mhhe.com/physsci/chemistr...sh/hybrv18.swf
http://en.wikipedia.org/wiki/Orbital_hybridisation

This is basic general chemistry 101...
cgk
#21
May30-12, 03:39 PM
P: 419
Quote Quote by phoenix:\\ View Post
What do you mean it is not scientifically based? As for a reference, am I not good enough?!
There is no proof by authority in science.

But in any-case, here you go:

http://www.seas.upenn.edu/~ese111/Hybridization.pdf

...

This is basic general chemistry 101...
From the first link you post:
sp HYBRIDIZATION

This involves making linear combination of s and p atomic orbital to form molecular orbitals that are directed along certain directions. This leads to the so called covalent bonding.
ouch... it hurts.

No, but seriously: Don't take those introductory texts too seriously. It is not uncommon that they are written by people who themselves do not have a deep understanding of theory (just for reference: That does not mean that they are not good scientists; just that you cannot assume that a typical organics professor has any concept of what a "Slater determiant", a "molecular orbital" or a "covalent bond" actually is, and should take their theoretical explanations with a grain of salt).

Regarding "tetrahedral implies sp3": For example, tetrahedral coordination is also found in coordination complexes and these are most definitely not sp3 hybridized. And even in covalent complexes, tetrahedral coordination can result for any number of reasons; but expecting a hybridization to occur in later than 2nd row atoms is normally not called for, for the reasons DrDu already explained earlier in this thread.

To get a clearer picture of those issues, you might want to read Kutzeniggs "Chemical bonding in higher main group elements" (http://dx.doi.org/10.1002/anie.198402721 ).
phoenix:\\
#22
May31-12, 09:52 AM
phoenix:\\'s Avatar
P: 74
Don't take those introductory texts too seriously
It isn't that I am taking it too seriously, it is just that I am telling the other poster, for his general chemistry course what to expect. I know it is just a mathematical model trying to understand how certain molecules would interact/bond, but my point here isn't being solely focused on the uselessness of going past sp, or up to d orbitals, rather, as said before, if posed the question of it (previous post stated "theoretical framework") then you could use a simple way of getting what it may look like based on the mathematical framework developed by Pauling.

As noted before: "This is basic general chemistry 101"..., not an overly advanced course. And, in the U.S. this is taught the exact way those links state, we aren't taught or some of us aren't told that going beyond the second row is useless, usually we are given a bunch of question of a bunch of chemical molecules and are told to figure out its hybridization... However, at least in organic chemistry it is rather different. The professor I took organic chemistry with only stressed that the sp2 hybridization was only valid and we didn't deal with anything beyond that. However, we did touch on sp3 of carbon-hydrogen bonds though, but that isn't what I am trying to discuss here.

Thanks for the link though. I appreciate being more knowledgeable of chemistry. But, one thing, I can only view the abstract...
DrDu
#23
Jun1-12, 03:01 AM
Sci Advisor
P: 3,560
As noted before: "This is basic general chemistry 101"...
Kurokari doesn't seem to be from US. So I think it is quite irrelevant what may be taught in a specific class, what counts is a correct understanding of science.
Having done my thesis in molecular physics I share the folling complaints with many theoretical chemists:

1. Why are introductory chemistry students treated with mutilated theories of bonding they don't have the mathematical means to understand instead of being taught chemistry?

2. Why do introductory texts perpetuate even those concepts from Paulings books (which are still apedagogical masterpieces and a source of scientific insight) from the first half of the 20th century which have been proven wrong or seriously modified since then when quantitative checks of the predictions became possible with the introduction of computers?

I think the dominance of Pauling in introductory chemistry is - not too surprisingly - especially an US problem.

As far as the article by Kutzelnigg (who wrote many pedagogical articles trying to correct some of the most serious theoretical misconceptions among chemists) I fear you either have to buy it or get it from your library.


Register to reply

Related Discussions
What kind of reaction is hybridization. Chemistry 5
Can the concept of hybridization be applied to what we consider ionic, Chemistry 6
Hybridization states of the 8 orbitals (*) of Xe and Os Chemistry 3
Hybridization @___@ Biology, Chemistry & Other Homework 1
What is the hybridization of C in R - N=C=O Chemistry 5