Crestfallen Studios

Actually, i'm simmering on the inside...not quite a boil..just...miffed >_<

So...today started out really good...got up at a decent time, went down to the local cable company's office...and picked up my cable modem and self-installation kit. Went to class...had a riveting lecture on Organic RXN mechanisms (we're starting to get into nucleophillic substitutions and stuff) then went home to set up my cable modem. So...connection was easy...as it should be....then I pop in the CD to set up the actual ISP stuff.

Everything's running smoothly until it trys to find me a default gateway....and everything just kinda goes downhill. Tried a few things, and then gave up and called them. Basically got a response that I needed their permission etc. to set it up, so I got that, and then the guy notices he's not detecting a signal coming from me.....this is not a good sign >_<

As it turns out, it's something with the actual cable line...like it might not be set up for broadband, or the previous owner might have had a connection that wasn't disabled, or the line is filtered....*grumble* So, now I get to wait til Saturday when the cable guy comes out to check things out >_< Hopefully it's an external problem...because if it's something with the wiring in the house...I'm going to get charged for the visit -.-

Oh well....at least I got dinner with my girlfriend since she handed in her qualifying exam today...so...I guess the day wasn't -all- bad. Also got a little productive with some music and cleaned up something I was working on over the weekend hehe

I got to here and begin to skimming


nucleophillic substitutions

I got 1 quick step that 'll help you find a defualt connection:
get an ax and beat the shit out it then walk away happy...or play starcraft as protoss and build lots of gateways; the'll both work i guess; ones a pun and ones a quick fix


and what the hell is nucleophillic substitutions

nucleophillic substitutions:

The study of reaction kinetics is an important factor in synthesizing compounds in chemistry labs. By applying the differential rate law, a chemist can determine the order of a reaction and the rate constant by experimentally plotting the data of the reactant(s) change in concentration versus time. Determining the rate constant through use of integration can be used to determine the activation energy needed for a reaction to overcome the activated energy barrier. The project was supervised by Dr. Edward Turos, Department of Chemistry.

It is a subject involved in organic chemistry (According to my teacher, a chemistry major from UCLA who worked in laboratories, organic chemistry is one of the most difficult subjects out there.). Anyway it also involves Calculus 2 (subjects such as antiderivatives) in order to graph the reactions. If you want the link click here http://www.math.usf.edu/mug/AB69a.htm

update: as it turns out there were indeed filters on the cable line, so the tech came in today and removed them. I am once again happy. *huggles his broadband*

And as for the nucleophillic substitution stuff, Basically, a nucelophile (a compound attracted to the nucleus i.e. positive charge) comes in on what's called a backside attack. It collides with the target molecule, and another molecule is kinda knocked off when the bond gets broken.

In a nutshell, (rough example) Br* + CH2OBr -> Br*CH2O + Br

It's kinda interesting because when this happens, the molecule changes structurally. In otherwords (looking at a tetrahedral shape) If you look at the molecule going around counterclockwise It has a certain order. (say left handed) after this backside attack, the molecule becomes right handed, so the structure actually shifts.

er....this page probably explains it better.

http://www.chemhelper.com/sn2.html

Vaylos wrote:
And as for the nucleophillic substitution stuff, Basically, a nucelophile (a compound attracted to the nucleus i.e. positive charge) comes in on what's called a backside attack. It collides with the target molecule, and another molecule is kinda knocked off when the bond gets broken.

In a nutshell, (rough example) Br* + CH2OBr -> Br*CH2O + Br

It's kinda interesting because when this happens, the molecule changes structurally. In otherwords (looking at a tetrahedral shape) If you look at the molecule going around counterclockwise It has a certain order. (say left handed) after this backside attack, the molecule becomes right handed, so the structure actually shifts.

Oh god, take me now.

Vaylos wrote:And as for the nucleophillic substitution stuff, Basically, a nucelophile (a compound attracted to the nucleus i.e. positive charge) comes in on what's called a backside attack. It collides with the target molecule, and another molecule is kinda knocked off when the bond gets broken.

Is the bond relatively strong, resulting with a huge release of energy? And what nucleus is the compounded attracted to?

Aw hell I'm getting flashbacks to organic chemistry . . . . . . I need a drink . . .

First off, I'm going to apologize for how much what you're about to read may or may not confuse you.

Going to -try- to keep this relatively simple, since I don't know how much chem ppl have had, and I want to avoid causing too many headaches here hehe. Also keep in mind i'm a student, not a teacher, and I'm not entirely sure if i'm 100% correct on this. Furthermore, if chemistry really isn't your thing, I would advise not reading below this line. Oh, and it's 3am as I type this, so screw grammar and spelling

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The strength of the bond/release of energy depends on the atoms that are bonded within the molecule. Organic chem is mostly carbon-based, So in many cases the bond that is broken is a bond between a carbon and a hydrogen or halogen. or other nonmetal.

As for what nucleus the nucelophile is attracted to, it's not actually attracted to the nucleus itself, so it's a bit of a misnomer in my opinion. Rather, the compound is attracted to positive charges or partial charges in polar molecules. The incoming nucleophile has to be able to "see" the nucleus of the central atom/carbon (or chiral center) on the molecule it's hitting. This is why steric hinderance is an issue, because large/bulky groups tend to "hide" the nucleus from the incoming nucleophile. There was a nice video we had in class on it, but it can only be accessed from the campus labs :/ Tried to make some acii art of it, but the spacing got messed up so all you're getting is text heh There are other factors involved as well, such as the types of solvent used, how good the release group is, polarity of the target molecule, how strong the nucleophillic attraction is...it's really a lot to think about.

Given CH3R in a tetrahedral geometry: where R is a release group:

1. An incoming nucleophile is attracted to the positive side of the molecule. However, it will attempt to bond with the central carbon.

2. As Nucleophile gets closer, the Hydrogens bonded to the carbon will actually be repelled.

3. Hydrogens are forced into a planar configuration, and there is partial bond making with the Nucleo - Carbon and partial bond breaking with the Carbon - Release group. The R group leaves, and the H's will continue moving until they re-establish a tetrahedral configuration.

4. The R group is moved away, and the N is bonded to the Carbon now. This type of reaction happens from the opposite side of the Release group, so it's called a backside attack. This basically -inverts- the structure, so if there was a Cl and an OH group instead of 2 of those H's, the structure inverts, and instead of being left handed, it becomes the opposite.

The problem with steric factors is this:

Say instead of hydrogens, a carbon is surrounded by 3 CH3 groups, and an R group. The bulky CH3 groups attached make it harder for the Nucleophile to "see" that central carbon, so the reaction will slow, or in extreme cases, just not happen at all.

This is about as basic as I can get for what I was trying to talk about.
I'm probably sounding like gibberish Some of this stuff is hard for me to choke down, so I can't imagine what it's like for anyone who hasn't completed the college general chem sequence I tried to keep things kinda simple though. I'm not exactly the best person to ask about this kidna thing since i'm just a student heh

i'm tired now and sleep calls -.-

omg... and I thought Physics was boring, pointless and confusing...

It's chemistry...

If you dojn't know how to keep chemistry biology and physics apart, then heres some tips:

If it moves then it's biology.
If it smells then it's chemistry.
If it doesn't work then it's psysics.

I like chem, because we made things explode

Explosives are malways a blast.

lol mmmm explosions. We got to burn stuff in chem 3 because we had to do flame tests Look at color of flame to determine what ion was present. They were purty No open flames in organic though We don't want to literally blow up the lab room, and most the solvents and crap we use are extremely volatile like methyl chloride. (Fume hoods are a good thing)

I love flame tests!

My teacher was doing it and was like "flame Testing.... "

It was wicked.