The Periodic Table

DHMO

13:19

> Annulenes are monocyclic compounds containing alternating ring double bonds, such as benzene, but of different sizes.

chemgapedia.de/vsengine/vlu/vsc/en/ch/12/oc/vlu_organik/…

Loong

13:40

@DHMO In IUPAC nomenclature, [n]annulene is only used for n>6.

DHMO

@Loong so that page is basically worthless?

user228700

@DHMO

DHMO

@Kaumudi so, the two electrons in that bond would have to be assigned to O

right?

user228700

Which bond?

DHMO

@Kaumudi the bond between the top hydrogen and the oxygen

user228700

13:52

@DHMO Those two electrons belonged to O to begin with, right?

DHMO

@Kaumudi well, in the formal charge system, they are split equally

Ramanujan

@DHMO can't we think f.c. as atom having (more or less) elections relative to original atom elections?

DHMO

@Ramanujan yes

Ramanujan

Then O should have 0 FC?!?!?!

DHMO

@Ramanujan why?

notice that we are only drawing the valence (= outermost shell) electron

O originally has 6 electrons in its outermost shell

user228700

13:55

@Ramanujan Dude, no, look at the diagram. It's one electron short (Remember that as @DHMO has kept reminding us, the electrons are split equally, so it has only one electron for each bond)

DHMO

@Loong two question:
1. why is there only 15 orbitals?
2. where is the lowest energy orbital made by 5 s orbitals in phase?

user228700

@DHMO OK..? What is that other system?

Ramanujan

@DHMO now I know iam reply tired and need some sleep ( I was thinking O has 8e)😨😈😫😴

DHMO

@Kaumudi so now, the 2 electrons in the bond belong to oxygen

@Ramanujan ok

@Kaumudi I thought you already told me what the other system is. That's the system which accounts for the electronegativity

user228700

@Ramanujan It does have 8 e-, but only 6e- in its valence shell.

DHMO

13:57

I don't think it has a name, if a name is what you are trying to find

Ramanujan

@Kaumudi yes,feeling sleepy

user228700

@DHMO Right. OK. So, wait, what I've learned from this discussion is that a. I gotta figure out what kind of rule to use (expanded octet etc ) eben BEFORE drawing the diagram

user228700

b. Coordinate bonds are to be introduced only when the atom in question can't expand its octet.

user228700

But when I was asking about the charge thing, I meant how to know which atom has the charge even before drawing the structure and figuring out the formal charge..?

user228700

@Ramanujan Shubh Ratri.

DHMO

14:02

@Kaumudi you don't need to know which atom has the charge before drawing the structure

9-BBN

Hello

user228700

@DHMO OK. I think my brain is dying again (Symptoms: I'm turning blind etc.) I'ma go and get a lot if practice. Thanks so much for all ur help :-)

Ramanujan

@Kaumudi not going now,after. Some time

DHMO

@Kaumudi you're welcome

9-BBN

What are you speaking about ?

DHMO

14:04

@9-BBN we were talking about charges in a molecule/ion

9-BBN

Jan said "The number of question marks is inversely proportional to the question's perceived seriosity." I found something which is true in economy, the amount of money exchange between two town is proportional to the product of their population and inversely proportional to the square of the distance between them

And then newton is back and can have a Noble prize in Economy :P

Loong

@9-BBN hm, "inversely proportional to the square of the distance"? That's a bit surprising since the inverse-square law usually applies to point sources in three-dimensional space, but towns are only distributed on a surface.

9-BBN

It was a study made in France I found it fun

Loong

So, in France, they also throw money into the air and dig it into the ground. ;-)

DHMO

@Loong Could I ask you a question?

Loong

14:19

@9-BBN And what does "between two towns" mean in France anyway? There is only Paris and province. ;-D

@DHMO You can try. :-)

user228700

@DHMO: Are u busy? I have another question (regarding the charge thing; I'm so sorry :'-()

DHMO

@Loong so, (trans-)butadiene, being in symmetry group C2h, have the py orbitals combine easily

I'm wondering how the px and pz orbitals combine

@Kaumudi go ahead

9-BBN

@Loong LOL

Loong

@DHMO Are you thinking about a hybridization or an MO model?

user228700

@DHMO Why I asked about how to find the charge of an atom is 'cause of situations like when I attempt to draw the lewis dot structure of molecules such as $ClO_3^-$. Can u help me with this?

DHMO

14:24

@Loong MO model

@Kaumudi just use the electronegativity model

the formal charge model is worthless (trigger warning)

user228700

@DHMO And then...what? OK, I follow the steps; count the number of valence electrons and it comes out to be 26. Then, I need to make the bonds but how to do that w/o knowing about this charge thing? ie. How many bonds should I make to the oxygen atoms?

DHMO

@Kaumudi determine the charge beforehand

using the eelctronegativity model

@Kaumudi the total valence electron number is useless

user228700

OK, so I figure that it must be one of the oxygen atoms that gets the charge...so...? Hang on, what are the steps that u follow to write Lewis dot structures?

DHMO

how many bonds do each atom need?

I virtually ignore the valence electrons

user228700

Hey, but answering that question doesn't help me very much; Cl needs just one bond really.

DHMO

14:28

continue

user228700

..?

DHMO

what about the Os?

user228700

Can u please tell me the steps that you follow to write the Lewis dot structures?

user228700

@DHMO They each need two.

DHMO

@Kaumudi except the O-, which only needs one

now, Cl expands octet

@Kaumudi oh, I just place the central atom and surround it with every other atom

user228700

14:30

@DHMO Riight. Should've figured that before writing.

user228700

OK, I'll try doing that. Sigh, I can't believe I suck so bad at this. Thanks again...

DHMO

because usually only the central atom expands octet

so i just satisfy the side atoms

Loong

@DHMO single lobes of the p orbitals can interact with another single lobe along the chain and form the C–C sigma bonds

DHMO

@Loong but they are not on the same line... is this allowed?

Loong

@DHMO yes, you have to find a suitable linear combination of atomic orbitals

DHMO

14:35

@Loong could you draw one of the MOs formed by px or pz please?

Loong

something like an sp2 hybrid orbital

DHMO

@Loong Are we talking about butadiene?

how does anything from px or pz ever have C3 symmetry...

@Loong can we not hydrbridize them?

Loong

14:50

@DHMO Well, you saw yourself that not all orginal atomic orbitals have the ideal geometry for interactions with other orbitals. You have to find new combinations. Orbital hybridization is just a simplified model approach for that.

DHMO

@Loong is that a part of the MO theory?

I always thought the other orbitals would just be non-bonding

orthocresol

@Rubisco We meet again.

Rubisco

@orthocresol YOU

This . . . is impossible.

I already sent my minions to hunt you.

orthocresol

A man you can bait with a chat message is not a man we can trust with moderatorship.

Rubisco

Not THOSE yellow ones, the other purple ones

@orthocresol A man who baits with a chat message is not a seal we can trust with modship.

orthocresol

15:06

Of course, because a man isn't a seal.

Rubisco

That's besides the point.

And you seem to be a hybrid.

Todd Minehardt

hi folks

Rubisco

Who's folks?

ANOTHER CANDIDATE? Readies sword

Todd Minehardt

@Rubisco @orthocresol @Loong

Rubisco

'ello

Loong

15:07

@ToddMinehardt hi

Todd Minehardt

i think you scared away a few candidates, @Rubisco :)

Rubisco

I did?

Todd Minehardt

you martens are pretty scary looking

2

Rubisco

Very related pic.

Oh, actually related.

I wanted to propose a name to the name meta post myself. Should I?

Todd Minehardt

yes, for our German friends - marder, i believe?

oh, yes, please do

@Loong - is der Marder correct?

Loong

15:12

@ToddMinehardt yes

Todd Minehardt

i still think it would work for @Rubisco :)

Der MARderator

Rubisco

0

A: Let’s choose a definite name for our favourite molecule, in case he gets elected as a mod!

Since y'all like to play with my initials, what about just my initials? I propose "MAR".

Loong

They do this with your car:

Rubisco

Oh no

Loong

Rubisco

15:14

I am NOT a marten.

Prolly.

Todd Minehardt

now the mudslinging comes out, typical election politics :)

Rubisco

I'd do that to Ortho's car if you want.

Loong

@Rubisco The seal mobile?

Rubisco

Yah

It's not as exciting as you think.

Polar bears can crack it open.

And they're an Earth away.

CowperKettle

Is there a good Chem Kinetics series of videos on YouTube (long videos or series of videos)?

I want to listen to some as a backdrop

I found a couple, but the lectors slip into Hindi now and then

Unfortunately, I know only about 20 words in Hindi

Todd Minehardt

15:18

Rick Astley - Never Gonna Give You Up

►

CowperKettle

(0:

Todd Minehardt

:)

Rubisco

:]

CowperKettle

Dhanyavaad

DHMO

poll: how do you pronounce the "al" in methanal ?

A. nation**al**
B. ration**ale**
C. others

CowperKettle

15:22

@Rubisco Mamad

Rubisco

How to Pronounce Methanal

►

@CowperKettle If I knew people'd pronounce it correctly, I definitely would've.

DHMO

@Rubisco hard time distinguishing methanol and methanal

Rubisco

yes, it's sometimes hard

DHMO

so we stress the "al" by pronouncing it like rationale

orthocresol

I call it formaldehyde.

DHMO

15:26

@orthocresol nice

Rubisco

@orthocresol ugh, formaldehyde people

Aaron Abraham

6

Q: Soaps come in different colours. Then why is foam always white in colour?

The question is the title itself: Soap comes in different colours. But why is soap lather always white in colour?

everyday-chemistry

DHMO

> Each drop, or at least each several drops, are essentially a step of a random walk for the incoming light waves[2].

Aaron Abraham

@DHMO We'll slug it out here ;P

DHMO

@AaronAbraham what is the random walk?

Aaron Abraham

15:29

I stopped once I reached there, actually :P

TO THE LINK!

DHMO

@AaronAbraham hint: it is not answered in the link

Aaron Abraham

> And that’s why clouds are white. Each drop, or at least each several drops, are essentially a step of a random walk for the incoming light waves[2]. If the cloud is very large compared to the size of the step (which is on the order of a few times the distance between drops), then the light is much more likely to wander back out to the same side of the cloud it came in than it is to wander all the way to the other side.

DHMO

@AaronAbraham yes, this is what i quoted

what is the random number generator?

Aaron Abraham

Now where's that?

> This concept generalizes to all kinds of light scattering objects.

DHMO

> And that’s why clouds are white. Each drop, or at least each several drops, are essentially a step of a random walk for the incoming light waves[2]. If the cloud is very large compared to the size of the step (which is on the order of a few times the distance between drops), then the light is much more likely to wander back out to the same side of the cloud it came in than it is to wander all the way to the other side.

here

Rubisco

15:31

@Martin-マーチン Nathing

Aaron Abraham

Random number generator?

DHMO

@AaronAbraham "a random walk for the incoming light waves"

Aaron Abraham

Where'd you see that ?

DHMO

what is causing the random walk?

@AaronAbraham ignore the "random number generator"

Aaron Abraham

The presence of the innumerable water droplets in the cloud @DHMO. I think that was clear from the article.. ._.

DHMO

15:33

@AaronAbraham what does the light wave exactly do? what bends the light?

you would say the droplet bend the light

my question is how the droplet bends the light

Aaron Abraham

@DHMO (sigh) Buddy...........................ever heard of something called, refraction?

Todd Minehardt

Rayleigh scattering

Aaron Abraham

Oh hi @Rubisco

I didn't see you there..

DHMO

@AaronAbraham so my answer is wrong because i only included TIR but forgot refraction...

Rubisco

I get that often

!!greet/@Kasey

Chemobot

15:35

Welcome to The Periodic Table @Kasey! Here are our chat guidelines and it's recommended that you read them. If you want to turn Mathjax on, follow the instructions in this answer. Happy chatting!

Aaron Abraham

You're an enzyme...you're easy to miss. Live with it.

Auf wiedersehen peeps.

Todd Minehardt

hi @DHMO @AaronAbraham

DHMO

@ToddMinehardt hi

@AaronAbraham satisfied?

Rubisco

15:52

8

A: How do I formally disprove this obviously false proof?

Hint: $1=1+0\neq 0+0$. Study $P(1)$.

They should really think of something so this bull crap stops.

That's not even Yahoo Answers answer.

Rubisco

16:05

-1

Q: Android SE website bad answer (spam)

found an answer that should be flagged, but not enough reputation to do so. http://android.stackexchange.com/a/159894/186920

discussion

O.O

user228700

16:22

Anybody here..?

Rubisco

This answer is gibberish, hence abusive. Please flag and move on. Especially you, @Ortho. Don't edit red-flag answers. — Rubisco 12 secs ago

@Kaumudi No

orthocresol

@Rubisco Yes, but I do not like seeing walls of text.

Rubisco

Then leave a link to it in chat so we nuke it faster.

orthocresol

Yes, but I can still see it even after you get rid of it.

Rubisco

@orthocresol No, you'd see something else.

And even if you do, when you change the answer, the mod can't evaluate the flags correctly.

orthocresol

16:35

Is that spam?

Rubisco

But it's abusive.

Same goes for abusive posts.

orthocresol

Can I edit it after it's deleted?

Rubisco

Yes, IIRC.

When I had 10k powers.

orthocresol

Ok, that's good enough.

Oh, I see what you mean.

I thought that was only for spam flags, because I've only seen spam.

Thanks

Rubisco

Now candidate Prompt leads with double digits.

orthocresol

16:52

Nothing that I didn't already put in my nomination blurb :)

CowperKettle

17:13

> We adjusted the pH of the solution to 6–8 with 5 M solution of hydrochloric acid and 5 M alkaline solution.

Is it better as "basic solution"?

wow

orthocresol

Alkaline is OK.

CowperKettle

@orthocresol Really? Maybe it was just "basic", without an alkali metal?

Loong

@CowperKettle If you can say that is was "5 M", you should be be able to reveal what base was actually used.

Aaron Abraham

@DHMO Yep :3

CowperKettle

@Loong There's no mention of that in the translation

I mean, in the Russian text

Aaron Abraham

17:22

Whoops, hi @ToddMinehardt. Yeah, considered Rayleigh scattering as well. Thanks!

CowperKettle

@Loong So it would be never mentioned thus in a procedure description, without naming the base?

I'd write a letter to the authors then

@Loong If it is "5M alkaline solution", is it also odd? Shoud the nature also be revealed?

> We next added 14 mg of powdered alkali to the same tube. (earlier in the text)

Would this also be wrong?

Loong

In case of "5M alkaline solution" it may not be important whether it was NaOH or KOH. But it should not be so difficult to write that down.

комильфо

@CowperKettle But in case of 14 mg, it does matter.

CowperKettle

@Loong D'oh.

I should write to the authors again

Loong

@CowperKettle at least you know that it wasn't NH3

Or it was @orthocresol with the magic NH3 powder again.

orthocresol

18:01

Haha

Loong

What does he want to do, and where is the problem?

-1

Q: How to build cyclohexene/ E cyclo hexene and bridgehead double bonds and bridged bicyclic systems of less than 6 carbons using molecular models?

I tried to use molecular models to build cyclohexene and (E) cyclohexene and bridgehead double bonds, and bridged bicyclic systems of 6 carbons but failed. Is it possible to build the aforementioned things and are there videos of how to do it?

organic-chemistry

It doesn't look so terrible as it sounds.

And that's probably the other one:

Aaron Abraham

@Loong I hope you're a physical chemist ._.

0

Q: Why is it impossible to attain a temperature of Zero Kelvin (Absolute Zero)?

We were dealing with the Third Law of Therodynamics in class, and my teacher mentioned that it is physically impossible to attain a temperature of zero kelvin (absolute zero). When we pressed him for the rationale behind that, he asked us to take a look at the graph for Charles' Law : His ar...

thermodynamics temperature

Rubisco

@AaronAbraham There's something about this on physics.SE

Aaron Abraham

I only care for a chemist's point of view @Rubisco :P

Loong

18:22

@AaronAbraham The engineering point of view is even simpler: In order to cool your sample, you need something that is cooler than your sample.

Aaron Abraham

OH.MY.GOD

THAT IS BRILLIANTLY SIMPLE

Loong

So, in order to cool your sample to 0 K, you would need a coolant that has a temperature below 0 K.

Aaron Abraham

@Loong I DON'T REGRET VOTING FOR YOU. I NEVER WILL!!

Salute

Loong

The physical chemistry point of view is actually related. However, it refers to entropy.

Third law of thermodynamics

The third law of thermodynamics is sometimes stated as follows, regarding the properties of systems in equilibrium at absolute zero temperature: The entropy of a perfect crystal at absolute zero is exactly equal to zero. At absolute zero (zero kelvin), the system must be in a state with the minimum possible energy, and the above statement of the third law holds true provided that the perfect crystal has only one minimum energy state. Entropy is related to the number of accessible microstates, and for a system consisting of many particles, quantum mechanics indicates that there is only one unique...

Aaron Abraham

But wait...why can't we have something at a temp. below 0K

Loong

18:26

@AaronAbraham At 0 K, all molecular motion stops. You cannot be slower than that.

Aaron Abraham

@Loong Could you turn that into an answer?

Loong

You might get multiple answers with different aspects.

If not, I could write something.

Aaron Abraham

I doubt anything would beat your answer....seriously.

It's so lucid

Anyways, Gute Nacht @Loong I'm off to bed (it's midnight, where I'm from)

Loong

@AaronAbraham I see. So have a good night.

Wildcat

18:53

=^.^=

Time to call the KGB! XD

Loong

noted.

Wildcat

called :D

Loong

~~But we are FSB now.~~ Isn't it FSB now?

Rubisco

Froggy Sentimental Bastards?

Wildcat

@Loong yep

from 1995

Loong

19:00

I thought so.

Wildcat

KGB was just renamed basically a couple of times in 1990s.

Loong

Do they still have the Lubyanka?

Wildcat

19:33

@Loong If you mean the building, then no.

Lubyanka Building

The Lubyanka (Russian: Лубя́нка; IPA: [lʊˈbʲankə]) is the popular name for the headquarters of the KGB and affiliated prison on Lubyanka Square in Meshchansky District of Moscow, Russia. It is a large Neo-Baroque building with a facade of yellow brick designed by Alexander V. Ivanov in 1897 and augmented by Aleksey Shchusev from 1940 to 1947. == History == === Origins === The Lubyanka was originally built in 1898 as the headquarters of the All-Russia Insurance Company. It is noted for its beautiful parquet floors and pale green walls. Belying its massiveness, the edifice avoids an impression of...

FSB headquarter is located on the same Lubyanka street, but that is a different building.

Loong

I see.

Hi @Mel

9-BBN

20:07

Can someone explain me why to add NH4Cl at 10% after a reaction between RMgX with an ester ?

My final product is not soluble in water

And in the organic phase I don't really havethings which are soluble

Loong

@9-BBN What about all the Mg(OH)2?

Melanie Shebel

Heya

9-BBN

Why NH4Cl instead of water?

Loong

@9-BBN You need water for the hydrolysis of the R-O-MgX. But you need HCl to dissolve the resulting Mg(OH)2.

9-BBN

Oh yeah sure ! Thank you @Loong !

Loong

20:17

And since you are making a tertiary alcohol, HCl may be too strong; so you only use NH4Cl.

9-BBN

No it is ok because I have an acetal in my last molecule and I want to keep it

:)

Loong

@9-BBN Have you made a Grignard before?

9-BBN

Yes

Loong

ok

9-BBN

I add fructone on para bromo Mg anisole (IUPAC nomenclature in their ***) :P

Loong

20:24

Hehe. Do your compounds smell nice?

Rubisco

Yes, they're French.

Loong

haha :-D

9-BBN

Fructone well it is not so bad and the final molecule i will do I don't know

I worked in fragance application lab this summer at GIVAUDAN

It was not so bad

Loong

!!img/ethyl (2-methyl-1,3-dioxolan-2-yl)acetate

Chemobot

9-BBN

20:27

If you know the name of the tertiary alcohol I will have give me lol

Loong

@9-BBN I have seen and smelled it in Grasse. :-)

9-BBN

I smelled butyric acid it was ...

Loong

and of course the lavender fields around Grasse

orthocresol

Sometimes I'm really not sure if I'm reading a question or a story.

9-BBN

@orthocresol which one ?

orthocresol

22:18

The one about absolute zero.

@AaronAbraham

> This is quite obvious Aaron, it's a pity you weren't aware of it; don't worry maybe if you read up Nernst's works you wouldn't be in such a conundrum. Take my daily routine for example... *". I had to run, before the nerd said anything else. Now I did Google this up, and well, the internet's done pretty good job of muddling my brain further.

This entire section is not really useful to read.

Secondly, comment section should really be reserved for comments about the question. If you want to ask about something unrelated, use chat. Or at the very least, clean the comments after you are done.

Of all unrelated things to talk about, politics especially should really be avoided.

I'm sorry for being that guy, but someone had to say it.

I edited your post so that you can see what I would consider to be "clean".

orthocresol

23:11

Rationale for this is: SE is not a forum. Main site is a place for questions and answers, no decorations, no unrelated discussions, and it's not a place for conversation.

Questions should aim to be succinct and direct, for two reasons: 1) more beneficial to future visitors. 2) much easier for potential answerers to read.

In terms of quality, the ideal Q&A should really be entirely impersonal. Obviously that doesn't always work and there is always some leeway, but please don't take it too far.

The question itself is good and in its current form deserves to be +1'd.

So, I +1'd it. :)

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