The Periodic Table

Martin - マーチン

4:44 AM

!!xkcd/1756

!!flip

(┛ಠДಠ)┛彡┻━┻

!!xkcd/1756

@Chemobot a little sleepy today, he?

ringo

So many close votes starting huh @Martin-マーチン

Especially on these older questions

Martin - マーチン

4:54 AM

yeah... i usually don't go through the queues, but that number was quite high, so i took a look

ringo

I don't really disagree that many of them should be closed, it's just weird how many there are

And how did we let them get by without closing in the first place?

I can't really complain though... so close to getting my Steward badge ;)

Martin - マーチン

I have very mixed feelings about many of these. I tend to rather let them open. From what I can tell someone edited a bunch of titles removing buzzwords and put some flags up at the same time

gannex

5:13 AM

hey is anybody home?

I really need to know if DMSO is a pi donor or sigma donor. If anybody could help me out, it would be super appeciated.

Martin - マーチン

5:48 AM

Dimethyl sulfoxide

Dimethyl sulfoxide (DMSO) is an organosulfur compound with the formula (CH3)2SO. This colorless liquid is an important polar aprotic solvent that dissolves both polar and nonpolar compounds and is miscible in a wide range of organic solvents as well as water. It has a relatively high melting point. DMSO has the unusual property that many individuals perceive a garlic-like taste in the mouth after contact with the skin. In terms of chemical structure, the molecule has idealized Cs symmetry. It has a trigonal pyramidal molecular geometry consistent with other three-coordinate S(IV) compounds, with...

primarily sigma donor, I would say

gannex

6:14 AM

Hmm. I guess I've been getting lost in the literature. Should've just gone to the wiki. The thing that's confusing me though is that I have the DFT calculated MOs for DMSO and the HOMO looks like a pi* orbital (antibonding about the s-o bond) that would overlap with dxz.

There are however a bunch of other lower energy levels that would do a sigma-donor interaction... could it be that it would be an MO other than the HOMO that would do the donation?

Martin - マーチン

6:32 AM

@gannex just found your question... good one ;)

gannex

6:44 AM

I'm feeling a little stumped.

from IR-spec, I know that the S-O bond gets weker when DMSO bonds at the oxygen, but I want to justify this based on the MO and right now all I have is the general idea that withdrawing e- density from the oxygen makes the S-O bond more polarized (lower bond order resonance form)

CowperKettle

8:12 AM

Good day!

1-glycine -- what could this mean?

Some isoform of glycine?

ah, it was l-glycine

or L-glycine; probably levo-rotated

should one use the capital "L", or is "l" okay?

CowperKettle

8:29 AM

If the whole sentence is "l-Glycine", is it right to capitalize just "Glycine"? The sentence is inside a table cell

Martin - マーチン

8:43 AM

@CowperKettle that doesn't really make sense... glycine is not chiral

user228700

Hey everyone :-)

CowperKettle

@Martin-マーチン Thank you! I wonder what it can be then

@Martin-マーチン The Russian sentence is "l-Глицин"

Martin - マーチン

@Kaumudi Happy Pizzamas!

CowperKettle

A couple of lines lower, there's "l-Proline"

user228700

@Martin-マーチン Happy Pizzamas! :-D

Martin - マーチン

8:48 AM

I don't speak russian, I can't help there...

CowperKettle

3

Q: Are all amino acids except glycine chiral compounds?

Specifically, I was thinking of the case where the R group is a carboxylic acid functional group or an amine group. Then there would not be a chiral carbon atom. Is there a restriction on what can be an R group that I am missing?

user228700

I've a very quick question. If someone were to ask you "What is the difference b/w a vapour and a gas", would u say "That question is meaningless"?

CowperKettle

@Martin-マーチン Basically it says "l-Glycine"

@Kaumudi a gas is the vapour phase of a substance, probably

user228700

@CowperKettle Uhh, I think that could be phrased a little better, but yes, there is no inherent difference, is there?

CowperKettle

> Most amino acids occur in two possible optical isomers, called D and L. The L amino acids represent the vast majority of amino acids found in proteins. Glycine, however, because of its simple structure and two hydrogen atoms at the α carbon, does not have D- and L-stereoisomers. It is unique among the 20 standard amino acids in not being optically active and is only in the L form.

THERE IS NO D-GLYCINE.

(from Yahoo Answers; is this right?)

Martin - マーチン

8:51 AM

@Kaumudi it's a really bad question, but you might find some starting points there: chemistry.stackexchange.com/q/61383/4945

but for what it's worth I would say vapour is the same as gas

user228700

Oh God xD

user228700

Yes, alright, this website clears up the fog surrounding these two terms very well:

user228700

differencebetween.com/difference-between-gas-and-vs-vapor

user228700

Excerpt:

user228700

> Gas can be taken as a broader term that encompasses vapor in its fold. Vapor is then particular types of gas.

user228700

8:55 AM

Anyhoo, thanks :-) Are u going to buy any Pizza John March from DFTBA?

Martin - マーチン

@CowperKettle well, technically since glycine is achiral, there is neither L- nor D-form, so this cannot be correct

CowperKettle

@Martin-マーチン I see! Thank you! I'll make a note in my original Russian document

Martin - マーチン

@Kaumudi i'm not sure if I can... it's a bit complicated with shipping and paying for stuff :(

CowperKettle

> And also, don't confuse the D-L system with d- and l- naming. d- and l- is the exact same with (+) and (-) notation.

I don't get this. So there might be "l-glycine" but not "L-glycine"?

12

A: What is the difference between D and L configuration, and + and -?

The D-L system corresponds to the configuration of the molecule: spatial arrangement of its atoms around the chirality center. While (+) and (-) notation corresponds to the optical activity of the substance, whether it rotates the plane of polarized light clockwise (+) or counterclockwise (-). ...

user228700

9:31 AM

@Martin-マーチン Yeah :/ I've never bought anything either :-( Have u participated in the P4A?

Martin - マーチン

nope... just silent consumer

user228700

I've been a nerdfighter these past 2.5 years and I've participated in both P4As :-) My family doesn't use credit cards, so I wasn't able to donate :-( I did watch and vote on a bunch of videos tho! The livestream is also very exciting!

user228700

You should definitely check out the livestream at least! It's absolutely amazing :-D

user228700

I think it's on...Nov 9th, 10th and 11th this year. Not sure tho.

Martin - マーチン

It's December this year projectforawesome.com

Aaron Abraham

10:09 AM

Hey @ortho, is a username like this even allowed?

-_-

You're Mod/God ! You must be able to do something about it. o.o

Wait, what the hell is 'Pizzamas'? O.o @Martin @Kaumudi

Martin - マーチン

@AaronAbraham I find it very entertaining :D

Aaron Abraham

@Martin o/

flattered

=*_*=

Martin - マーチン

The History of Pizza John!

►

Aaron Abraham

@Martin-マーチン Wait Mart, you're God here too ._.

Pizza John, huh?

Martin - マーチン

well... caretaker is more fitting

Aaron Abraham

10:15 AM

So that's what @Kaumudi's using as the display photo! I just assumed she was a pizza-eating-communist ._. Whew

or a communist-eating-pizza

whichever works ;)

@Martin Ever been to akihabara? ;)

Martin - マーチン

lol...

Aaron Abraham

Whaat?

Martin - マーチン

yeah I've been, it's a money-eating monster

Aaron Abraham

XD

Always Confused

Why cold-drinks are so pungent? Just because of CO2?

Aaron Abraham

10:21 AM

So, what manga did ye buy ;)

@AlwaysConfused "pungent" in what way?

Martin - マーチン

It's great though, noisy, sometimes dirty and a lot crowded

i didn't buy manga there... just playing games and stuff

Aaron Abraham

You and @Jan are NOT the same XD.

Wait, @Martin, where exactly in Japan are you? O.o

Always Confused

@AaronAbraham 1. if I keep the nose near orifice of bottle; 2. The burps come out after consuming some amount of cold-drinks (Like Sprite, Coca-Cola, Pepsi et cetera).

Martin - マーチン

about two hours north of tokyo

Always Confused

That are burningly pungent. Isnt?

Aaron Abraham

10:25 AM

@Martin-マーチン M.A.R tells me you're on permanent vacation ;)

@AlwaysConfused Well yeah ._. But CO_2 by itself couldn't do that though.

Martin - マーチン

well... I am working though...

Always Confused

So what other thing cause that?

Aaron Abraham

@Martin-マーチン Oh yeah! "Computational Chemist" :P

Always Confused

Especially the burps that come out after consuming cold-drinks.

user228700

@AaronAbraham :-P Yes, I'm a very passionate nerdfighter.

Aaron Abraham

10:27 AM

@AlwaysConfused If you could ping me the ingredients used to make Cola, I could probably tell ye ._.

Perhaps Phosphoric acid?

user228700

Anyhoo, is this argument sound:

Aaron Abraham

NO

Wait, what argument?

Sorry, I have this habit of 'jumping the gun' ;/

user228700

> "An increase in surface area will let more liquid to evaporate but it will also allow more vapours to re-enter the liquid and thereby, condense. At equilibrium, the increased surface area will have caused equal increases in the rate of evaporation and condensation. So, a change in surface area doesn't change the vapour pressure."

Martin - マーチン

@AaronAbraham what's with the quotes man?!!! ಠ_ಠ

Aaron Abraham

@Martin-マーチン CALM DOWN MART! I didn't mean it! (Heck, the last time a German got angry, it started a World War!)

Martin - マーチン

10:30 AM

@Aaron !!gun

Chemobot

(ﾒ▼▼)┏)ﾟoﾟ)

Aaron Abraham

@Kaumudi At equilibrium is the key ;)

Martin - マーチン

;)

Aaron Abraham

Yep, it's right

@Martin-マーチン MG43?

or a StG44?

user228700

Yes, alright, thanks :-)

user228700

10:31 AM

That ^ BTW, looks nothing like a gun o.O

Martin - マーチン

!!gun

Chemobot

……┳┓o(-｀Д´-ﾒ )

Aaron Abraham

The Machinegewehrs are scary o.o

@Kaumudi It is very 'gun-like' XD

Martin - マーチン

!!flip/!!gun

Chemobot

(╯°ਊ°)╯︵¡¡ƃnu

ლ[☉︿۝)७)७︻̷┻̿═━一︻̷┻̿═━一

Aaron Abraham

10:33 AM

searches for the right emoji

Martin - マーチン

there are a couple of different ones, but it's random

just as the tables

Always Confused

An empty 7UP bottle shows sweetened carbonated water, acidity regulators-330, 331, 299? (scratched out), Preservative-211, added flavour (natural). Btw 'hidden secret' about cold drink is a popular gossip (myth/fact?) however I'm interested what is source of this characteristic 'burning' effect.

Aaron Abraham

Maybe the phosphoric acid in it volatalizes out?

@Martin （╬ಠ益ಠ)

Always Confused

I don't know cold-drinks contain phosphoric acid.

Aaron Abraham

@Martin-マーチン (I honestly, couldn't find a better emoji, sorry)

Always Confused

10:36 AM

Its ok. Should I ask it in Chemistry.SE?

Aaron Abraham

@AlwaysConfused webmd.com/osteoporosis/features/soda-osteoporosis

Martin - マーチン

@AlwaysConfused I'm not sure, but there might already be a question like this

Aaron Abraham

Yeah, Ask and ye shall receive, seek and ye shall find

Go do some seeking buddy ;)

Martin - マーチン

@AaronAbraham japaneseemoticons.me

Aaron Abraham

@Martin-マーチン Gee thanks!

Martin - マーチン

10:38 AM

the question might be deleted because it was not well received...

maybe check bio, too

and health...

Aaron Abraham

@Martin-マーチン That might be unlikely ._.

Wait, there's a Health SE??

Oh right there is!

Martin - マーチン

Aaron Abraham

I've joined ^_^ Danke @Martin

Martin - マーチン

;)

Aaron Abraham

@Martin So, what's the situation now? Is Jan coming to Japan any time soon?

Martin - マーチン

10:43 AM

I guess this is something you'd better ask him. I only know he wants to

havn't heard more gossip

Aaron Abraham

@Martin-マーチン The last time I did, he said he wasn't done writing/typing out his thesis ._.

Martin - マーチン

i bet this hasn't really changed

3

Aaron Abraham

XD

@Mart Between Physical, Inorganic and Organic, which one's your specialty?

Always Confused

@AaronAbraham Okay but my one was not about health impact but was about cause behind that burning-effect. However that link you provided; mentions nothing about phosphoric acid. The webpage suspects a link between osteoporosis and kola and keeps non-kola drinks (sprite, mountain-dew etc); which too have that pungent-effect.

So far I know; kola is a plant-product. (en.wikipedia.org/wiki/Kola_nut)

Martin - マーチン

@AaronAbraham computational ;)

Aaron Abraham

10:48 AM

@AlwaysConfused Whoops, bad link. Try this one: fooducate.com/…

Always Confused

I wish to ask it on Chemistry.SE if there is any green-signal.

Aaron Abraham

@Martin-マーチン（╬ಠ益ಠ)

@AlwaysConfused You want to know what causes it? Then by all means go ahead and ask. However, if you want to know why you get that burning sensation, then go for Bio or Health ._.

Martin - マーチン

@AlwaysConfused if you explain it thoroughly then go for it... just make sure you are understood

and show your research

Aaron Abraham

@Martin-マーチン So I'll take that as 'Physical Chem.' then ^_^

Martin - マーチン

@aaron I don't like labels like that...

most of the time i spent on catalysis which ist right in between all of them

Always Confused

10:52 AM

No not that signaling part I'm just asking about the constituent in sprite, 7up, etc that cause this 'burning burps' and burning smell.

Aaron Abraham

@Mart why no like labels you?

Martin - マーチン

usually you have organic reactants, organometallic catalysts (and/or transition states) and you are basically looking at thermodynamics

Aaron Abraham

@AlwaysConfused Burning smell?

2

@Mart Well that bodes well for me :D Mind if I ping you every now and then if I have a Thermodynamics query?

(Of course, I won't expect an instant reply)

Martin - マーチン

do so, but you might have better luck talking to the people around here that are learning stuff right now ;)

Aaron Abraham

@Mart I only care for a German's point of view ;)

> most of the time i spent on catalysis which ist right in between all of them

;)

Your true nature Mart ;)

@Kaumudi So how'd KVPY go O not-a-malayali-who-speaks-malayalam? (Unrelated: The heck's a "nerdfighter" ? O.o)

Anyways @Mart Tschüβ o/ I'm off!

Martin - マーチン

11:00 AM

bye o/

user228700

@AaronAbraham Dude, I'm a Malayali for God's sake.

user228700

I can't write KVPY-I'm a dropper. What about u?

user228700

Oh, just google it. (Nerdfighter, I mean)

Always Confused

@AaronAbraham Why? did you never observed it whenever you consumed cold-drinks? (Maybe the smell is wrong word... I should use 'burning sense'). Isn't that occurs?

And not me alone... all other (at least my family members) feel all cold-drinks too-pungent; and when I drink these (such as in an occasion) ; I never dink fresh. I put the glass on table for few minutes, shake it slightly so that some portion of pungent gas go out, and then I drink it.

Your second link fooducate.com/… mentions phosphoric acid... it migt be phosforic acid

Always Confused

11:31 AM

@AaronAbraham Thanks for your effort.

Jan

12:36 PM

@AaronAbraham Why would we be? @Mart isn't from Bavaria ô.o

Zhe

2:26 PM

@alwaysconfused aren't you just talking about CO2?

Ugh, this question: chemistry.stackexchange.com/questions/62295/…

1,3-feeds

3:35 PM

1

Q: I know that we mind the buzzwords but does that mean every single incident of each buzzword must be removed from every title?

Some time ago, I decided to post a Q&A self-answer question explaining some of the basics of point group usage. I titled the question: What are point groups, and how can they help me at a low level? Today, I realise that this title was edited. The edit summary read Change title (remove ...

discussion specific-question buzzwords

Jan

4:16 PM

@ortho @everybody quick, suggest a question I can bounty D=

orthocresol

hmm...

I'll tell you if I find something good

Loong

5:24 PM

Is this a trick question, or is it based on a wrong premise?

-1

Q: A tank contains isoflurane, at a pressure of 1.5 atm and 5 ∘C. What is the pressure of the gas,in atmospheres, warmed to a temperature of 29 ∘C?

A tank contains isoflurane, an inhaled anesthetic, at a pressure of 1.5 atm and 5 ∘C. What is the pressure, in atmospheres, of the gas is warmed to a temperature of 29 ∘C, if n and V do not change?

homework gas-laws

Isoflurane is a liquid under these conditions.

orthocresol

6:59 PM

@Loong "Hey, let's try and think of a random gas to make our ideal gas law question sound more interesting." "Oh, I've heard of this anaesthetic before! Let's use it."

orthocresol

10:46 PM

@hBy2Py I saw your correction of my "ran" to "run". After thinking about it for 10 minutes I can't decide which is correct and I'm even more confused than I was before I started thinking about it. :D

I trust you on it, though ^^

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