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3:27 AM
Do the 2p orbitals of F and F+ have the same energy level?
 
 
4 hours later…
7:06 AM
hullo!
Can someone lend me a hand with this, please
0
Q: Deriving the unimolecular rate constant using the RRK model

getafixWas reviewing some of my physical chemistry lectures and attempted a a derivation of the unimolecular gas phase reaction using a calculation based on the RRK model (Rice-Ramsperger-Kassel), and ran into some trouble half way into the derivation. My Derivation I have a unimolecular gas phase re...

 
 
2 hours later…
8:49 AM
@getafix I would, if I knew anything about it. :(
I just don't like kinetics
 
9:12 AM
yeah we did this in a bit of a rush, a week before our finals and I did not really get it. Fortunately did not turn up, but I am determined properly learn it this time haha
 
9:34 AM
can someone explain me the spectrum continuum of hydrogen?
 
10:28 AM
@DawoodIbrarBilandkhel what do you mean?
 
11:03 AM
@orthocresol would you be able to answer my question?
 
11:43 AM
@user34388 I dont think so
When you solve the schrodinger equation, the potential terms would be different..
 
 
2 hours later…
user116211
2:02 PM
@getafix Just a side-note; this is not the standard symbol $<<;$ it's this $\ll\;.$
 
strctly speaking it would be hartree-fock equations, not schrodinger, but yeah
 
2:21 PM
True
my bad
 
2:42 PM
I see...
 
Oh, I can edit deleted community wiki meta posts. :-)
 
@Loong aren't you a mod?
 
@user34388 I am not a mod on Chemistry.
 
@Loong then why can you edit those?
 
Everyone can edit community wiki posts. I just wasn't sure whether this still works when the post is deleted.
 
2:54 PM
I see
 
And there was a deleted 30000-character answer in the sandbox, which can be unwieldy when you can see deleted posts.
 
user116211
@Loong O.o
 
user116211
Can you have a snapshot?
 
user116211
That would be mammoth!!
 
@MAFIA36790 I have just replaced the deleted text with a single line.
It was this test:
 
user116211
2:59 PM
@Loong Which language is that? Pretty jumbled.
 
In publishing and graphic design, lorem ipsum (derived from Latin dolorem ipsum, translated as "pain itself") is a filler text commonly used to demonstrate the graphic elements of a document or visual presentation. Replacing meaningful content with placeholder text allows designers to design the form of the content before the content itself has been produced. The lorem ipsum text is typically a scrambled section of De finibus bonorum et malorum, a 1st-century BC Latin text by Cicero, with words altered, added, and removed to make it nonsensical, improper Latin. A variation of the ordinary lorem...
 
user116211
@Loong Had absolutely no idea of that ;/
 
user116211
Klingon is better ;P
 
For graphic design and typesetting, it has to look like typical text.
 
user116211
ohh.
 
3:35 PM
Hi! I may have answered my own question, but I need someone tell me if I am right..or wrong for that matter.
1
Q: Deriving the unimolecular rate constant using the RRK model

getafixWas reviewing some of my physical chemistry lectures and attempted a a derivation of the unimolecular gas phase reaction using a calculation based on the RRK model (Rice-Ramsperger-Kassel), and ran into some trouble half way into the derivation. My Derivation I have a unimolecular gas phase re...

 
What would happen if tert-Butyllithium is mixed with water?
My guess is (CH3)3CLi + H2O -> isobutane + LiOH
But I am not sure if this reaction is reversible
Wiki says it reacts with water, but almost every solute in water reacts with water...
 
Don't think it would be reversible.
Also, I dont recommend trying it..
 
Then how does this evaporate water?
I don't think reacting counts as evaporating?
 
evaporate water?
 
4
Q: Why is this question not overly broad?

JanThis question was posted 2 days ago, closed yesterday as being too broad and reopened today. The question has never been edited so its contents are the same throughout. I wonder why people voted to reopen it and why that vote subsequently went through. The question asks whether there is a chemic...

"I’m pretty sure that some tert-butyllithium will do the trick [make water evaporate extremely fast] as well."
 
3:47 PM
ahhh
The reaction should be extremely vigorous..and exothermic.
So the heat generate would probably evaporate water..
 
I see
 
and like i said, would not recommend trying it
 
Not that I would
 
Usually, it would catch fire in air before it touches the water.
 
I see
 
3:54 PM
That too..
 
@Loong How do I indicate a catalyst above the arrow of reaction in LaTeX?
 
@user34388 $\ce{A ->[{text above}][{text below}] B}$ should work
 
@Loong thanks
@Loong Does iron oxides react with water to form iron hydroxides spontaneously?
If so, is the reaction reversible?
 
ah I am painfully close to unlocking a new privilege..sigh. A little more than 100 rep needed..
 
@user34388 That depends on how the iron oxide was prepared. If it was heated and has lost all water, the process is not reversible at neutral pH.
 
4:03 PM
@getafix I would like to upvote your posts but I'm afraid it would trigger serial voting
@Loong in what environment is it reversible?
 
@getafix 👍
 
@user34388 It's reversible when the iron oxide was prepared by condensation of iron hydroxides and as long as it is still fresh.
 
Why does hydrogen peroxide make iron rust faster?
I'm guessing the oxygen?
 
@user34388 kind of you to offer haha
currently trawling for questions i can answer..or maybe i should do that romorrow it is 1.05 AM hmm
@pentavalentcarbon Hullo there! been a while
 
@getafix I upvoted five, @pentavalentcarbon can upvote another five
but it would still not be enough
 
4:07 PM
@user34388 Oh wow! thanks so much..I really wasnt expecting that haha
and yeah hydrogen peroxide is an oxidising agent
rusting is essentially oxidation..so that's why haha
 
@getafix alright, thanks
@getafix If I want oxidation, then why don't I just apply permanganate?
 
I am in no position to upvote most questions and answers on this site
so forgive me if I don't
 
@pentavalentcarbon Don't worry about it, it is not necessary..
 
Someone downvoted my answer :/
 
@user34388 well how do you want to apply permanganate? rubbing some crystals onto solid iron obviously wont work that well..
 
4:12 PM
@getafix acidified permanganate
 
The struggle is real on all counts.
 
it's the oxidizing agent commonly used
strong oxidizing agent
oh, my use of "apply" confused you. as you see, I'm not native
 
yeah okay..that could work, i am sure you can write out the redox equations yourself most probably
 
@getafix but why don't people use it? too dangerous?
 
I never knew deliberately causing rust was a thing..?
 
Haha I see..
well i think permanganate should work similarly..
As far as why people dont use it..cant say..
maybe harder to procure than peroxide?
Ive never given it much though
 
I thought it was used for some things?
 
@pentavalentcarbon i'm referring to making iron rust
 
Ah, ok.
 
hmm interesting though..
ive never really thought about how I can make things rust faster..
usually its the other..preventing corrosion..haha
 
4:24 PM
6KMnO4 + 9H2SO4 + 10Fe -> 5Fe2O3 + 6MnSO4 + 3K2SO4 + 9H2O
After 10 minutes of balancing...
@getafix ping
I guess other oxidizing agents such as the one I just used would dissolve the iron
 
seems right..Mn goes to +2 to Fe goes from 0 to +3
 
which is why hydrogen peroxide is used instead?
 
Sorry, cant check your numbers..too late in the night
 
I've checked them already
Would the presence of silver speed up rusting?
Theoretically iron sacrificially protects silver... but is silver too unreactive to have that effect?
@getafix
 
hmm I am not quite sure what you mean..like silver ions in solution, a silver coating on the iron..some sort of silver iron alloy?
anyhoo getting real late for me..gotta full day tomorrow, catch you later. I am sure someone here will be able to help you with your questions
 
 
1 hour later…
5:59 PM
@getafix my secret guide to gaining rep on chem.SE: 1. ignore real life 2. spend all day on SE in order to answer questions immediately when they pop up :)
i think the organic chemistry questions tend to garner the most rep
any answer that explicitly says "d-orbital participation in hypervalent compounds is minimal" also gets lots of upvotes
also "hybridisation is not an actual physical process"
 
user116211
@orthocresol the universal truth.
 
@MAFIA36790 sometimes i kind of pity the people who start off learning that and then come here and are told that it's not real
 
user116211
@orthocresol aww.... O.o
 
user116211
@orthocresol to avoid that, you need to read good literatures.
 
introductory chem is a bunch of simplifications... if we could teach schrodinger equation and wavefunctions to high schoolers that would be infinitely preferable, but i dont think they would understand it
 
user116211
6:09 PM
I started with Atkins; and he was explicitly clear on this.
 
i dont think i would have!
good for you
 
user116211
@orthocresol Will not say learn but actual visualisation is must; you can start with introductory courses like Feynman Lectures; they will save you from ages of miseries to be followed otherwise.
 
@orthocresol And, of course, give fast and short answers to short questions.
In one case, I found an old question with a mediocre answer and spent half a day on a new answer with two complete calculations and four different references. → +1 for the other answer.
For my next answer, I simply copied the relevant passage from an IUPAC report: → +15
 
@Loong shhhhhh, don't tell them!
 
and that is why I will never have oodles of rep
so it goes
 
user116211
6:20 PM
@orthocresol I faced hard times on those topics for the first half of my std. XI th year; fortunately I got those books to read which although slowed me from the mainstream studies, enlightened me a lot and saved me from such misconceptions.
 
@MAFIA36790 Most people aren't so fortunate
 
user116211
@pentavalentcarbon Go to maths... you can swim in rep-river.
 
i think this is one of my shorter answers with +9
9
A: Why amino acids (Zwitterion) become either negative or positive at low and high pH solutions?

orthocresolFirstly a note about terminology. The word "terminus" is reserved for the N- or C-termini of a polypeptide chain. For a free amino acid, you should refer to the carboxyl and amino groups as the $\alpha$-$\ce{COOH}$ and $\alpha$-$\ce{NH2}$ groups respectively. Anyway, the -$\ce{COOH}$ group is ac...

 
@MAFIA36790 Bah I'm terrible at math.
 
i screenshotted a table from ms word.... lol... time to mathjax-ify it before sleeping
 
user116211
6:22 PM
@pentavalentcarbon Who says to answer? Just ask! Even if you ask nothing, there is a fixed +1 for that ;P
 
user116211
Wait, @ortho, I today did a mathjax-exercise in the morning:
 
@orthocresol I guess that answers the question...
 
@orthocresol I have one answer at +24 that essentially reads "$p=m\cdot v$".
 
@MAFIA36790 I would ask something stupid like "how is the dual space different from the Hilbert space" but 1. I don't need the answer and 2. I could just look it up in a book
 
user116211
1
A: Are electric fields produced by static electric charges different from those produced by time-varying magnetic fields?

MAFIA36790$$\begin{array}{|c|c|} \hline\textrm{True in Statics} &\textrm{True in General}\\ \hline \mathbf F = \mathbf E~= \dfrac1{4\pi\varepsilon_o}~ \dfrac{q_1q_2}{r^2}~\mathbf{\hat r} & \mathbf F= q(\mathbf E+ \mathbf v\times \mathbf B)\\ \hline \nabla \cdot \mathbf E = \dfrac{\rho}{\varepsilon_0} & \...

 
user116211
6:25 PM
@pentavalentcarbon ;P
 
@MAFIA36790 That is not an answer!
 
I'm horrible at physics!
 
user116211
The question is a bleh but I always wanted to make such a table.
 
user116211
@orthocresol no, not the physics! The Table!!
 
I don't understand any of it
 
user116211
6:26 PM
@orthocresol made that 10 ;))
 
That table is sexy though, I'm stealing it.
 
user116211
@pentavalentcarbon \o/
 
user116211
I love you @penta ;D
 
looking at LaTeX makes me feel all warm and fuzzy inside
 
user116211
;))
 
6:28 PM
I wish I knew more but you really can get by with knowing very little
 
yeah, I just google whenever I run into some problem..
 
user116211
Anyways,going to bed after completing a post; good night @ortho, @penta @Loong.
 
@MAFIA36790 good night
 
@MAFIA36790 well now you can reuse the table, maybe one day it will come in useful on a better question :D goodnight
 
bye bye 👋
@orthocresol you inadvertently taught me about \! the other day on a post of mine you edited
 
6:33 PM
@pentavalentcarbon haha, was it the one about molecular term symbols?
@Loong I don't have anything at +25 so far :)
 
yes
I don't know about MathJax, but in normal compiled LaTeX I have to use \, all the time to add space inside of integrals
so now I know another spacing character
 
@orthocresol liar
 
@Loong heh, the benzene answer isn't even that good actually
@pentavalentcarbon Yeah, I think I read somewhere before that to typeset integrals properly one needs quite a lot of spacing characters
I just can't remember where it was. It recommended using \! after \int and \, before the \mathrm{d}x.
 
Yes, I use it in both places...didn't know that it would be wrong for after \int.
 
I might have remembered wrongly
feel like I haven't typeset any integrals for a long time
 
6:39 PM
@orthocresol That \, before \mathrm{d}x is probably one of the most important spaces that isn't typeset automatically.
 
I definitely agree with that.
I'll test \! vs. \, soon.
@Seamus: the order is \!, \,, \:, \;, \quad, and \qquad. In units of mu (= 1/18 em, determined from the surrounding font size), their widths are -3, 3, 4, 5, 18, and 36. — Niel de Beaudrap Nov 17 '10 at 13:09
 
I even have it in my test answer:
1
A: Formatting Sandbox—please test stuff here $test$

LoongSpace: the final frontier. Comparison of space characters $\text{abcdefghijklmnopqrstuvwxyz}$ (normal text without spaces) $\mathrm{abcdefghijklmnopqrstuvwxyz}$ ab (no space) $\mathrm{a{\kern 1pt}b{\kern 1pt}c{\kern 1pt}d{\kern 1pt}e{\kern 1pt}f{\kern 1pt}g{\kern 1pt}h{\kern 1pt}i{\kern 1pt}j{\...

 
WOAH
that post is insane!
 
@pentavalentcarbon yeah, I forgot to mention that if you like seeing latex, that post has a ton of it
 
6:42 PM
@pentavalentcarbon just be thankful you don't have 10k rep
 
Why's that? People ping the crap out of you?
 
on that very post
i wonder what he was trying to do
 
Maybe I'm being dense but I don't get it...
 
10k lets you see deleted posts
 
@orthocresol By the way, MathType has the same problem. You have to manually insert a thin space before the dx. It's explicitly mentioned in the manual.
@orthocresol This one was even worse: meta.chemistry.stackexchange.com/posts/461/revisions
 
6:45 PM
@pentavalentcarbon as a result, you get to see a lot of junk
@Loong ...
 
OHHH I get it now. You can see it even though it's deleted.
 
@Loong I remember reading the \, before dx on SE, it was probably you
 
ugh you've taught me something else I'm doing wrong...maybe
1
A: Formatting Sandbox—please test stuff here $test$

orthocresol\newcommand{\md}[0]{\mathrm{d}} \frac{\md\hbar}{\md\pi} $$\newcommand{\md}[0]{\mathrm{d}} \frac{\md\hbar}{\md\pi} = 0$$ \md U = \md q + \md w $$\md U = \md q + \md w$$ Please don't murder me for not using the inexact differential sign. \langle \psi_1 | \psi_2 \rangle Doesn't look good on my ...

 
@ph13 You should have been warned by 18 hazard pictograms that this post is dangerous. — Loong Sep 16 '15 at 19:37
every time I read that I laugh
 
:-D
 
6:48 PM
this whole thing is gold
 
@pentavalentcarbon there is the new thread as well, meta.chemistry.stackexchange.com/questions/3077/…
 
I don't think I can contain myself anymore
 
Now finally for the proof that the fourth is zero, you need a little bit of multivariable calculus, and if nobody has done it by tomorrow, ping me in the comments and I will type it out. (It's 2 am here and I should really be off to sleep!) — orthocresol 58 mins ago
3am... okay... goodnight guys
 
@orthocresol good night :-)
 
`(.•.)´
 
 
4 hours later…
10:26 PM
Can someone explain why chemistry.stackexchange.com/questions/55196/… shows as being active today, but all of the posts and edits are from 6/19 or 6/20?
 
@pentavalentcarbon It was probably pinged by Community, as answer has no upvotes.
 
What does it mean to be "pinged by Community"? Mentioned in a Community post?
 
@pentavalentcarbon "Community" is a standard bot.
It does some stuff automatically on site
 
Ok, I knew about "Own community questions and answers so nobody gets unnecessary reputation from them" but not the others.
Is there any way to tell what it did?
 
"Randomly poked" :D
Dunno how as I can't see any edit there
 
10:34 PM
By power of deduction, then :)
 
Ah, I was looking for something like that, but couldn't find a link on the question page. I've never seen that before.
 
Hmm, this bot is quite powerful, has mod rights and I've seen it dupehammering questions.
 

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