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12:13 AM
Hi, everyone :-)
I've a quick question. I came across the following question on CSE:
When I saw the four options, I didn't think of actually adding a hydrogen to each compound or anything. Rather, I used this definition:
> "Heat of hydrogenation of alkenes is a measure of the stability of carbon-carbon double bonds. All else being the same, the smaller the numerical value of heat of hydrogenation of an alkene, the more stable the double bond therein."
So I tried to figure which of the given alkenes would be most stable.
 
Zhe
Stable relative to what?
 
It is clear that trans-2-butene is the most stable of all of them because in the first place, it has 6 $\alpha$ hydrogen atoms, so it has 6 hyperconjugative structures. Secondly, it's trans → less dipole moment, compared to the cis alternative.
Is this reasoning OK for a question like that?
@Zhe I...dunno .__.
 
Zhe
You have to be careful here
When you talk about stability, are your comparing them to each other?
Or to the corresponding alkane?
Also, why is dipole moment important?
@Kaumudi
 
@Zhe To each other, I think.
 
Zhe
Then that doesn't work unless all of the alkane are the same energy
 
12:29 AM
:-/ We haven't been taught exactly what it is we're comparing to. (Does it help to know that I've only just graduated high school?)
Dipole moment, hmm. We had been taught that the trans isomer is more stable than the cis isomer because the dipole meant in trans is basically 0 but not in trans.
...and I just learned that dipole moment doesn't really have anything to do with stability.
Awesome.
OK, I did find s'thing that matches what my teacher once taught me:
> "Dipole moment tells about the nature of the bond. Higher is the dipole moment, higher will be the ionic character of that bond and lower will be the covalent character of that bond.
If the ionic character is higher, then the reactivity will also be higher and ultimatly stability will be lower.
e.g hydrocarbons have no reactivity due to zero dipole moment while carbonyls are highly reactive (have dipole moment). Many aldehydes are very unstable."
 
1:11 AM
I...have a quick question again.
^ Why is that correct? (Given in my textbook)
 
1:33 AM
Does anybody know the relation b/w solvation and inductive & mesomeric effects?
 
1:59 AM
So I'm anosmic but there are a few things I CAN smell on occasion. Since smells are highly based on biological receptor things (not a biologist) and the odorous chemicals that are picked up by these receptors, I was wondering if there would be a way to determine links between the chemical structures of what I CAN smell. (I wanted to phrase this question on chem.se, but didn't how.)
 
 
1 hour later…
3:09 AM
@MelanieShebel It should be possible to list everything you can smell, but whether you could find a link between them would not be guaranteed. Furthermore to identify its binding to a specific receptor, you would first have to identify the receptor, characterise its structure (usually X-ray crystallography afaik), then either carry out some experiments to determine whether there is binding (there are many) or do some in silico molecular docking.
Proteins are really tough creatures to work with ;)
We like to talk down to biologists (xkcd), but you have to respect the work they do - biological experiments are a hundred times harder than chemical ones.
 
3:38 AM
@paracresol Cossack song of the day
I tried to translate it, because it is beautiful, but it's very hard
 
3:50 AM
Another one, much like the first
A funny march song. It starts all nice and patriotic about a captain and his soldiers. Soon the listener learns that the captain squandered the soldiers' money on booze and gipsey women.
"Sich Riflemen Song"
I translated it quite quickly
 
 
1 hour later…
5:17 AM
I can only smell roses, freshly made toast, and things cooked in butter. It's weird.
 
6:00 AM
Hlw
I would like to know that do both AgOH and Ag2O precipitate ?
 
 
2 hours later…
8:11 AM
Anyone there
 
 
2 hours later…
user116211
10:16 AM
Thanks @ortho; the comments are insightful; will check the link later.
 
@MAFIA36790 No problem, sorry for the delayed response.
 
user116211
No worries; sorry from me for bothering you; but the comments seem to be beneficial to the post. Thanks.
 
Well, it's not a bother!
And thus @MAFIA36790 vanished into thin air...
0
Q: How to draw hyperconjugating structures?please do help

Vivek Reddy how to draw hyperconjugating structures? Please explain

If MAR was here, he'd have a field day with this question
 
10:43 AM
I am comfused in below problem
Somebody can help me in that
In the above clainsen condensation reaction
Why the reagent marked does not attack the carbonyl carbon of other compound (given reactant)
 
 
2 hours later…
12:57 PM
> Whoever bites sodium, he is quick to learn chemistry the worst way possible; whoever learns chemistry the worst way possible, enters Heaven pretty quick. Thus, let us drink beer.
2
hmm
> The pH was kept at the needed level during culturing by feeding CO2 through the sparger when the medium turned alkaline and a 7.5% solution of NaHCO3 if the medium turned acidic.
 
^ O_o
:O
 
I'm not sure if I should use the word alkaline or basic
Good evening, @paracresol
 
Evening comrade! o/
It's 'bout 6:30 here...what about there @Cowper?
 
> The pH was kept at the needed level during culturing by feeding CO2 through the sparger in case of alkalization and a 7.5% solution of NaHCO3 in case of acidification. (is there an alternative to 'alkalization'? "Basification"?)
@paracresol 18:05 here
 
Oooh A half hour difference \o/
^^ O_o
Yekaterinberg?
 
1:07 PM
Does "alkaline" imply the presence of an actual alkali?
I still like "alkaline"
Yes, Yekaterinburg
BBL
 
@CowperKettle That'd actually make a good question on the main site ._.
@getafix o/
 
hullo!
 
PEG ;D
 
Sure ... Go on giving me false hope -_-
@getafix Doesn't the prospect of legally earning rep by posting an answer to the question even matter to you? ;D
 
1:14 PM
meh its okay
 
I'll write up an answer when I have time, but in the meantime you can satisfy your curiosity
 
...
@Cowper and his Luther rip-offs X'D
 
anyway, I think I should work or sleep
 
@getafix So jaya's dead...how very...anti-climatic ._.
@getafix Work ._.
Arbeit macht Frei, Work sets you free 3;D
Entrance to the Dachau Concentration Camp XD
@ortho o/
 
1:27 PM
@paracresol The picture is not from Dachau. That's Auschwitz.
 
@Loong What about this one?
 
@paracresol Looks like Sachsenhausen.
 
(I thought Arbeit macht Frei was unique to Dachau >.<)
@Loong How can you tell just by looking?!
 
@paracresol "Jedem das Seine" was unique to Buchenwald.
 
@Loong Damn! I was going to say that next XD
How about, Jedem das Seine, mir das Meiste ;D
 
1:38 PM
While we're on the topic of Arbeit, I thought this guy's username was uncannily appropriate:
4
Q: Why does the Gibbs free energy only correspond to non-expansion work?

ArbeitIt has been defined as the energy available for work other than expansion work. Why can't it be used for expansion work

 
:D
@ortho! I require from thee, ein piece of information!
 
@orthocresol Hehe. :-) Btw, ISO still lists $A$ as well as $W$ as symbol for work.
 
?
I'll stick to W...more intuitive ;P
 
@paracresol Didn't you have some related questions about BET once?
0
Q: Sign Convention BET

Aditya ShrivastavTomorrow is my exam , And I got a silly doubt. In this equation , Both of the Enthalpy are negative (Since exothermic). So If I want a High value of C , so The Enthalpy of Liquefaction should be higher than the heat of adsorption ?? Or I just don't have to consider the signs so the just rever...

 
Um...yeah
 
1:48 PM
> Please reply within 14 Hrs.
2
:-D
 
Nope...not that kind of question though :(
@Loong -_-
Damn, he's desperate XD
@Loong What day has the most traffic here?
 
@paracresol Usually Mon, Tue, Wed, and Thu have the most page views.
 
@Loong Could you single one out? (With the highest, of course ;) )
 
2:10 PM
@Loong I looked at those data, and I have no idea why on earth it peaks at ___day every week.
 
-_-
 
@paracresol What was it? Sorry, I was out.
 
@orthocresol @$$#*%!
@orthocresol Precisely what I asked Loong ._.
 
Oh, I see. Well, it's *****day.
 
Wed/Thu? Got it!
 
2:13 PM
3 mins ago, by orthocresol
@Loong I looked at those data, and I have no idea why on earth it peaks at ___day every week.
This message had three underscores, though.
 
Obviously, the gap for the weekend is spread due to different time zones.
 
@orthocresol I thought that was arbritary -_-
 
Ah, true. But why does it consistently peak at $n$-day, and not $(n+1)$-day, for example.
 
@orthocresol @$$#*%! -_-
 
In Chinese, the days of the week are literally "Day 1" through "Day 6", followed by "Sunday".
 
2:17 PM
I couldn't care less about China ._.
 
Like it or not, China's a world superpower now.
 
Patiently waits for Germany's Day :3
@Loong @Jan To this day...I still get pissed off hearing Germany doesn't have any nukes -_- Heck, even Pakistan has nukes :'(
 
Because the last time someone nuked someone, nothing bad happened.
3
 
 
3 hours later…
4:55 PM
For organic

 organic chemistry

Discussion for organic chemistry
 
@koolman ?
 
For who are interested in organic chemistry
Discussion
 
I see ._.
 
5:19 PM
I have 1 litre 2 molar Nacl solution... how much Nacl is there in 400mL . Let me clear my question.. I am not asking for regular calculation . I want to no that if there is xml Nacl in 400 mL. Than water is 400 -- xmL . Solve for x pls...
@DHMO.. r u free now ? :-)
 
@ffahim People don't normally calculate the amount of NaCl in grams O_o
*mililitres
I said grams...my bad.
 
A chemostat (from chemical environment is static) is a bioreactor to which fresh medium is continuously added, while culture liquid containing left over nutrients, metabolic end products and microorganisms are continuously removed at the same rate to keep the culture volume constant. By changing the rate with which medium is added to the bioreactor the specific growth rate of the microorganism can be easily controlled within limits. == Operation == === Steady state === One of the most important features of chemostats is that microorganisms can be grown in a physiological steady state un...
How is a chemostat different from just a bioreactor?
 
5:34 PM
@CowperKettle Well, according to wiki article a chemostat is a bioreactor, albeit it keeps the microbe count (more or less) the same ._.
Comrade o/
 
I wonder how this is achieved. Cells have a variety of "phases"
In their cell cycle, I mean. Maybe in a chemostat the main goal is to keep them in one phase.
 
Retain the ones in the same phase?
I don't think it simply freezes the cells in one phase ._.
 
I see. I should read up on this then.
 
The article does mention that the microbes have to be constantly removed.
@Hexacoordinate-C Salut O/
 
The variety of equipment is bewildering in biology.
 
5:41 PM
@CowperKettle It's like 10:40 there right?
 
lurk mode on
 
こにちわ
 
@paracresol yes
 
@paracresol Are you in New Delhi?
 
5:41 PM
Nope ._.
 
In Pakistan?
 
Oh right, you have access to the site analytics XD
@CowperKettle ABSOLUTELY NOT! -_-
 
No, I don't. I'm just guessing. Afghanistan?
Kazakhstan?
 
...
Wait, you have over 25k rep right?
 
no
800 rep
 
5:43 PM
:O
Bullshit -_-
Lemme check...
 
Laggy computer
:'(
 
@Hippalectryon hello :)
 
Hello!
 
@Hexacoordinate-C :-) hi
 
5:46 PM
@Cowper Oh yeah! ~800 rep
@Hippa o/
Didn't see ya there ._.
Looks like @Chemobot's all the rage now ;)
 
I see xD
 
Chat was flooded with "Thanks Hippa" XD
over the past week ;)
 
!!img/tea
 
Hold tight, I'm processing your request ... (╯ ͝° ͜ʖ͡°)╯︵ ┻━┻
 
Et benh il est pô rapide
 
5:51 PM
!!img/Thanks @Hippa!
 
@Hippalectryon pourquoi Chembot il arrive pas à charger ?
 
6:13 PM
srry was away
!!img/coffee
!!img/tea
@Chemobot y u slow
!!img/tea
 
@Hippalectryon Thanks! I followed the greeting message to the meta post and finally to the repository at Github.
I somehow managed to get it up and running, finally, with Imgur disabled at the moment, though. Thank you for writing the code!
 
!!img/tea
 
Hold tight, I'm processing your request ... (/ .□.)\\ ︵╰(゜Д゜)╯︵ /(.□. \)
 
!!tea
 
Hello, @Chemobot! I'm your descendant!
 
6:20 PM
:P
 
!!water
 
!!!img/water
:( y u no work
 
LOL
 
I'll debug it on

 Chemobot

Development discussion and testing of Chemobot. Possibly also ...
 
All the hype killed it.
 
6:27 PM
is it possible to have non-radioactive element above 120?
 
Can anyone access chemspider.com ?
 
Yes, I can.
 
:( I can't, I get redirected to rsc.org
 
Oh! Strange!
 
That's very weird
It seems to be why img/... doesn't work anymore
 
6:38 PM
 
user246160
Anybody here knows what are these type of compounds called ? orderbb.emolecules.com/search/…
 
user246160
If the O was replaced by N I know it is called Lactum...
 
7:00 PM
@TheStackExchange Lactone
Lactones are cyclic esters of hydroxycarboxylic acids, containing a 1-oxocycloalkan-2-one structure, or analogues having unsaturation or heteroatoms replacing one or more carbon atoms of the ring. Lactones are formed by intramolecular esterification of the corresponding hydroxycarboxylic acids, which takes place spontaneously when the ring that is formed is five- or six-membered. Lactones with three- or four-membered rings (α-lactones and β-lactones) are very reactive, making their isolation difficult. Special methods are normally required for the laboratory synthesis of small-ring lactones as...
 
user246160
@Hippalectryon Thanks a lot!
 
Zhe
7:20 PM
@TheStackExchange The amide analogue is called a lactam, not lactum
 
user246160
7:37 PM
@Zhe Okay...got it :)
 
Jan
8:26 PM
@orthocresol Hebrew does that, too, although they use their equivalent of day A, day B to day F followed by day Sh (shabbat) xD
@paracresol Some countries just feel that they need nuclear weapons for defence/preemptives/self-satisfaction/virtual penis length. Other countries fear their danger more and see the consequences of having nuclear weapons as more negative than positive. And believe it or not, some countries actually adhere to (some) treaties they signed.
@Hexacoordinate-C If that was French I didn’t understand a word of it =O
 
8:54 PM
@Jan I just had to check in my Pantone colours what "canary yellow" actually means. ;-)
 
Jan
@Loong Obviously, you’re not female ;)
 
@Jan The closest German standard colour is probably RAL 1016 Sulfur yellow.
 
Jan
The closest to [Pd(PPh3)4] or the closest to canary yellow? :D
 
The closest to canary yellow. I don't have a sample of Pd(PPh3)4.
 
@Jan you don't understadn "pô" ?
This is "pas" written like some people who have a strong accent tell it ;)
 
Jan
9:03 PM
Ah, that was exactly where I failed =D
 
Jan
9:18 PM
What is the preferred way in mhchem to force upright type for lowercase letters that the autodetection wants to italicise? Example: $\ce{H_a}$ (‘a’ is italicised) or $J_{\ce{a-c}}$ (the subscript should be identical to $\ce{a-c}$).
 
Jan
9:31 PM
!!!img/chloromethane
 
@Jan Chemspider is back online :-)
 
@Jan According to IUPAC, it's not acceptable to draw ethane as a simple line.
 
Jan
I always refer to ‘common use in (my) lab’ … ^^'
-1
Q: Use of acidified K2Cr2O7, dilute and alkaline KMnO4 and ammoniacal silver nitrate

MrAPI have seen many reactions in organic chemistry as well as inorganic chemistry involving acidified $\ce{K2Cr2O7}$, dilute and alkaline $\ce{KMnO4}$ and ammoniacal $\ce{AgNO3}$. My question is are these some special compounds and why are these used in so many reactions?

Does anybody understand the question? As in does anybody else see those reagents used in ‘so many reactions’?
 
9:50 PM
@Jan Hm, maybe the original (homework?) question wanted to see a comparison of oxidizing agents when applied to organic compounds, or a comparison of functional groups that could be oxidized. E.g. AgNO3+NH3 oxidizes aldehydes but not ketones, etc.
 
Really????
 
Jan
@MelanieShebel Good thing I left the chat as quickly as I ‘joined’. (I didn’t even see the full question properly)
 
It's just the demand that gets me. It's rude. I could have known the answer and wouldn't have helped, tbh!
 
Jan
= to be honest.
 
10:03 PM
Oh, sorry!!
 
rushim.ru/books/physchemie/… useful for who needs thermonynamical values of equilibrum
 
Nice desk
@Jan you speak Japanese now or Ron is ?
 
Jan
I speak animu or wiiabuu, depending on what you want to call it ;)
Nobody knows who, what or where ron actually is, except for his online times approximately correlating with US daytime schedules. And I haven’t seen any activity of his in a while.
(Assuming genders here based on name. Huge apologies if I’m wrong xD)
 
Jan
10:15 PM
Also, obligatory inb4 Loong tells us he knows everything about ron.
 
Oh really
@Loong you must speak if you don't want to finish in HF :-)
 
Jan
Well … for Loong to finish in HF, you first need to find out who Loong is and then find them …
 
Do you know where he is ?
:P
 
Jan
Probably in the colour checking thing.
 
???
 
10:24 PM
I bet she's speaking about your probil picture
 
Jan
Things you only get to see on metas: users with two silver and zero bronze badges. Damn, I was confused ô.o
 

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