The Periodic Table

Brian

02:41

@pentavalentcarbon What thoughts on Gentoo? (Most of my experience is on Debian, but I was forced into Gentoo when one of the computers I tried to install Linux on crashed out on boot with Debian.) Seemed more trouble than it was worth for all but high-end power users, wanting to optimize performance of everything.

@pentavalentcarbon And then there's the fun when you have things with conflicting dependencies. I now see the magic of virtualenvs, but haven't yet needed to figure them out.

user116211

03:05

0

Q: Basic Intro to Quantum Chemistry. Two Slit Experiment and Bohr Model

We just learned about the 2 slit experiment in Quantum Chemistry today, where electrons behave as waves when nobody is looking and behave as particles when they are being observed. So, what would happen If I were to observe an atom (such that all it's electrons now behave as particles instead o...

quantum-chemistry

user116211

@Martin-マーチン: What do you think of the above question?

user116211

Shouldn't it be migrated to Physics? It has nothing related to Chemistry

pentavalentcarbon

03:48

@Brian Based on my limited understanding of Gentoo, Arch is similar except the official repositories contain pre-compiled binaries. So, it's just like Ubuntu from that standpoint.

So, 99% of my packages are "official" ones that I haven't modified in any way, and things update normally.

Dependency management is never an issue; it's excellent. The package manager (pacman) is so nice to work with.

The nice thing is that compared to Debian/Ubuntu, packages are build using what amounts to a glorified shell script. There's a few other variables specific to their package building system, but you get used to it.

So, if I want to modify an official package (say, compile with more options or leave static libraries in), I update my clone of the official repositories, edit, make, install, and I'm off to the races.

A lot of the software we use doesn't exist in the official repositories, of course. I think the existence of the Debichem people is great. They might have packages for all the truly free quantum packages that don't require signing a license agreement.

So I've either written Arch packages to compile from source or re-package the Debian ones, since some things I still can't compile properly.

For software where I want multiple versions, I still use environment modules, but other things I just want the latest version and for it to work. So the system install is fine.

Martin - マーチン

06:48

@MAFIA36790 Agreed, not much about Chemistry. I don't have the time to do the research, but I think on physics.se there should already be a question along the lines "Why don't electrons fall into the nucleus?" I don't want to close it just yet, but you can push it into the queue.

12 hours ago, by IͶΔ

We VTC homework questions because we assume the OP is someone unfocused trying to get us do his job, rather than a baffled student eager to learn.

I am not sure this is true.

> That's the biggest mistake with this.
We're judging content from its OP.
It has never been that way in closure.
But now that we've dived in, we can't look back.

IͶΔ

@Martin-マーチン Be elaborate, get philosophical

Martin - マーチン

I'm not sure this is true either

IͶΔ

It was true when I started reviewing.

It's how I understood CV reviewing too.

Martin - マーチン

I'm not sure any more...

IͶΔ

Well, my opinion is scarce nowadays.

Martin - マーチン

06:53

I already moaned a lot about being nicer to the newcomers... I can't do it any more

IͶΔ

Why?

-1

Q: Schiff bases formation and conditions

I would like to know what kind of catalysis I must use to carry out the condensation reaction of 4,4'-diacetylbiphenyl with urea in order to obtain a Shiff base or the genearl conditions to achieve this condensation.

catalysis

Speaking of new users. :P

Martin - マーチン

Well, if the comm is not offering guidance, then... it's not happening

IͶΔ

@Martin-マーチン What do you want guidance to be?

Martin - マーチン

Sometimes I check the queue and find a question with four cv, yet none of them offered a comment

IͶΔ

I do see a bunch of close votes before I comment.

But I myself don't comment when I'm the 4th or 5th close voter, because the banner is there.

I don't wanna be redundant.

Martin - マーチン

06:56

Closing a question should be about improving it, at least if it's a new one...

IͶΔ

Also, @Mart I know the feeling.

The attitude I saw on meta.SE when I first got there about OT questions shocked me at first.

Martin - マーチン

no-one can improve the question if they don't know why we won't answer it

IͶΔ

But then I realized one should waste time for posts that are worth it.

Martin - マーチン

elaborate

IͶΔ

I'm getting relatively less feedback on my CV comments.

I'm sure you also feel that way.

Martin - マーチン

06:58

Well, I mostly don;'t get any feedback either...

IͶΔ

It's because someone who didn't even care to write a good title is highly unlikely to be trying to cooperate.

Martin - マーチン

in very rare occasion, someones says thanks and edits the question

more often i get "THIS IS NOT $%^& HOMWERKZZZZ!!!!"

IͶΔ

Yeah, and don't let that wear you off.

AFK I gotta do some cleaning

Back in an hour or less

Martin - マーチン

No probs, I have lots to do

Martin - マーチン

07:10

@Brian I just saw you comment on the HW chatroom. Since most of the HW is from new users (rep 1) that would not help. They need to be summoned to chat or gain rep 20. And with a sloppy HW this is simply not happening. So this idea is a dead end.

I kind of think that the only real approach is a faq like library for common hw questions. That of course should come with all the necessary explanations and a deeper insight, possibly more sources. And a couple of worked examples. This way we can close such "Is it correct?" question as duplicates. We still can tell them in the comments it's okay and if they want to know more they should check this post.

I believe that such questions open the possibility of encouraging new users to get active on the site. And active users is something we always need...

IͶΔ

@Martin-マーチン HW chatroom?

Martin - マーチン

that was some quick cleaning...

IͶΔ

I'm a fast worker.

Martin - マーチン

are you now...

IͶΔ

(/¯◡ ‿ ◡)/¯ ~ ┻━┻

Martin - マーチン

07:25

I think we need to say goodbye to the idea that we can help everyone.

IͶΔ

Whenever did we say hi?

Martin - マーチン

┬─┬ ノ( ^_^ノ)

what? hi?

ahh... ok

too slow today

skill patrol

you can't help all of the people all of the time

IͶΔ

I think everyone is meant in that way that we don't exclude anyone from getting help @Mart.

And that is what's happening.

Martin - マーチン

you can't help most of the people most of the time :/

IͶΔ

07:26

This content is visible to everyone.

Help shouldn't literally be helping people get answers to their question.

Martin - マーチン

obviously ... help is providing the necessary resources to help yourself

skill patrol

some people are beyond help

Martin - マーチン

lol

IͶΔ

Help is how someone with the same question as me finds the answer to their question even though they were neither the answerer nor the asker.

Martin - マーチン

That's what I said, isn't it?

IͶΔ

07:30

It is.

But you're getting weary, and that's worse than not answering a HW vampire.

Martin - マーチン

I have little time recently to answer anything... not even asking that question that is bugging me...

I am currently lost in code and can't think straight...

IͶΔ

@Martin-マーチン What question is bugging you?

@Martin-マーチン Think curly then. !!table

Bah, where is Chemobot?

Martin - マーチン

well, if i could tell you in a few words, i would have posted it already... :/

it needs research i can't do just now because codez

IͶΔ

(ﾉ＾◡＾)ﾉ︵ ┻━┻

Martin - マーチン

07:53

┬─┬ ノ( ^_^ノ)

IͶΔ

10:07

Two tips: 1) 8675309 is not just prime, it's a twin prime, and 2) if you ever find yourself raising log(anything)^e or taking the pi-th root of anything, set down the marker and back away from the whiteboard; something has gone horribly wrong.

3

$69^{\pi^\sqrt{5}}$

I <3 that

CowperKettle

10:52

I think there's a typo there.

The second reaction should have the reactant 2MnO4 marked with (2-), not just (-)

Still I can't understand why the products are so different between the acidic and the alkaline environments

Maybe I should ask a question about this on this site.

Martin - マーチン

@IͶΔ I love xkcd

skill patrol

Me too.

Martin - マーチン

$\displaystyle\lim_{8\to9}\sqrt{8}=3$

Brian

@Martin-マーチン Had forgotten that self-entry to chat required 20 rep. Good point.

@Martin-マーチン Yeah. The VTC reasons need to be changed, to avoid this kind of OP frustration, for sure.

Martin - マーチン

yeah someone had this discussion earlier, but it simply is impossible due to anti trolling protection

Well, we need to change them to keep our frustrations at bay, too.

skill patrol

10:58

if people want to troll they will find a way...

Martin - マーチン

yeah... but it's harder this way...

Brian

@Martin-マーチン This would almost require a new adjunct site, which would function ~completely differently from the SE model. It would be really awkward to try to cram into the Q&A structure.

Martin - マーチン

register, interact positively, troll...

IͶΔ

@CowperKettle Hmm, I think he wrote the overall reaction.

I'm kinda distracted right now tho'.

Brian

@Martin-マーチン Oh, absolutely. It's like WordPress just simply not allowing posting of images into blog comments. No one wants the kinds of images that 99.9999%+ of the comments would contain.

IͶΔ

11:01

@Martin-マーチン Which is hard even for the most proficient trolls

Trolls manifest language sites though. @Cowper knows it

Brian

It's not worth their time -- too many easier targets

IͶΔ

@CowperKettle The only thing you need to understand is starting looking for reaction mechanisms

Your curious mind needs a nicer thing to read than an online tutorial.

Brian

@Mart The whole time through this discussion I keep coming back to my positions stated here

4

A: Policy on questions in basic mediums

These sorts of questions touch on the fundamental identity of the community. What do we want to be on- and off-topic here? Do we want to be a resource that extends to educating raw beginners? Do we choose to take on the responsibility to guide every misinformed, misguided, or confused individual...

IͶΔ

No matter how good that might be.

skill patrol

@Brian true dat, the internet is full of easy targets ;-)

IͶΔ

11:03

Go grab a textbook on bases vs. acids @Cowper, and then learn for yourself what happens in reactions.

Not merely products vs. reactants scheme

Brian

Things come up that make me go, "Ahhghggh, it would be so nice if we could help people like that!"

"..... but it just. Isn't. Practical. with the SE model."

skill patrol

4 hours ago, by skill patrol

you can't help all of the people all of the time

IͶΔ

@Brian We all agree with each other but can't come up with something to do, or maybe feel too lazy/anxious/bored/worried to do so. It's like a bunch of kids around a cake not touching it because they worry they might finish it.

Brian

@skillpatrol Great minds, right? :-)

CowperKettle

@IͶΔ But there should be the charge (2-) at the MnO4, not just (-)

skill patrol

11:05

@Brian :-)

Martin - マーチン

4 hours ago, by Martin - マーチン

you can't help most of the people most of the time :/

IͶΔ

@CowperKettle I think he wrote the first and the last steps of the reaction

skill patrol

@Martin-マーチン rinse and repeat...

IͶΔ

The reaction above that is one of the steps.

Brian

@IͶΔ I don't think it's quite this. What we need is for the handful of us to be able to spend an hour and a half around a whiteboard hashing things out, instead of trying to cram the discussion through the drinking straw of a chatroom.

Martin - マーチン

11:06

@Brian I'll look through that again... I'm a bit exhausted tonight... i've been coding all day

IͶΔ

BRING IN THE WHITEBOARDZ

CowperKettle

@IͶΔ but in order to get "dark brown" we first should get "dark green", and this dark green chemical has the charge (2-)

IͶΔ

@Martin-マーチン That's exactly why we should discuss this. :P

@CowperKettle Yes.

Brian

@Martin-マーチン Hope it went well. Was up late myself revising some slides. Sleep well. (No time to copy the Japanese over from Google Translate, my youngest is clamoring for his breakfast. :-)

Martin - マーチン

Nah. One day a week I will make it to the supermarket in time...

CowperKettle

11:07

@IͶΔ anyway, I sent him a letter telling there might be a typo.

BBL!

Brian

@IͶΔ Could we use TeamViewer or something?

IͶΔ

@Brian Sure, whatever you guys'd like

\o

Brian

I don't know what's out there that might be helpful

Skype, maybe

Martin - マーチン

@Brian if you want to have a look: codereview.stackexchange.com/q/124354/92423 I think I did okay. It is a big improvement over the clutter I had before and I am ashamed to share.

okay... nighty night @all!

Brian

The challenge will be getting me & @penta on at the same time as @Mart and you, @IͶΔ and @MAFIA36790. Truly worldwide community!!

(Apologies to anybody I left out...)

IͶΔ

11:09

Sleep tight @Mart, don't let code bugs bite

skill patrol

cya later

IͶΔ

@Brian Japan vs. Iran vs. the US.

Is there anyone from Mars here?

Brian

WATNEY?!?!

IͶΔ

Mayhaps

Brian

<grin>

IͶΔ

11:10

@Loong's been to Jupiter before

2

Brian

Ok, gotta go dish some applesauce.

Loong

@IͶΔ ?

IͶΔ

Nothing

Brian

Hahahaha

<tips hat> later, all.

IͶΔ

\o

skill patrol

11:12

cya

IͶΔ

Back to watching an empty chatroom and dirt piling up

Brian

11:40

@Mart (or anyone), what's the rep level where regular users gain the ability to summon people to chat, if any? Could we ask SO overlords to implement a privilege, say at 500 or 1000 rep, enabling summoning-to-chat? That might be one way to draw low-rep "HW" askers into chat, to draw the interaction off the main site?

(Ok, actually leaving now.)

skill patrol

@Brian There is no rep level for the ability to summon people to chat.

Sounds like a good question for Meta.

IͶΔ

@skillpatrol No

Because it would be a dupe of

11

Superpings allow moderators to ping any user on the site from the chatroom, even if they haven't been in the chat in the recent past. If the superpinged user doesn't have a chat account because he lacks the required 20 reputation it will be created. This allows moderators to invite new user to th...

feature-request chat new-users privileges

skill patrol

@Brian The standard way to draw low-rep "HW" askers into chat is when the system creates a chatroom for discussions that go on for too long in the comment section of a question.

DeNiSkA

12:07

!!gun

hmm, no bot is alive :(

Brian

14:18

@skillpatrol Mm. That's pretty messy and unreliable, though.

skill patrol

@Brian messy yes, but how is it unreliable?

Brian

I don't want to have to wait until the SE system decides the comment thread has gone on too long in order to be able to kick things over to chat.

See Monica Cellio's answer to the question @IͶΔ linked

15

When a promising new user is having trouble making his first post and the community wants to help, we should make it easier for them to do so. I've seen chat work really well for this, and discussion in comments is not a pattern we want to set with a newcomer's very first participation on the si...

skill patrol

fair enough

There is also a "start a new room with this user" option on everybody's user profile link :-)

I see your point now.

The topic definitely warrants more discussion.

CowperKettle

15:29

@IͶΔ Turns out he did, the second line is the overall equation. But he wrote that he will rewrite that part a bit to remove the source of possible confusion.

> I can see that as I have written it, that is a logical assumption to make. In fact, the second equation is a properly balanced equation starting from manganate(VII) ions, and considering the overall reaction.

I will rewrite the text to remove the possible confusion. I will do that now ..

user116211

17:26

@IͶΔ: o/

IͶΔ

\o

user116211

Good night.

IͶΔ

Night?

Hippalectryon

17:41

This is not the kind of answer I expected for a bounty ._. chemistry.stackexchange.com/a/48783/5591

IͶΔ

._.

!!table

Chemobot

(ノ｀´）ノミ┻┻

pH13

17:57

@IͶΔ monster self answer post accomplished

IͶΔ

Yeah noice

Have 15 sweet repz

!!greet/@ramsay

Chemobot

Welcome to The Periodic Table @ramsay! Here are our chat guidelines and it's recommended that you read them. If you want to turn Mathjax on, make a bookmark of the link in this answer. Happy chatting!

pH13

@IͶΔ I don't think I get points if I accept my own answer.

ramsay

hii

IͶΔ

@pH13 But still get points from upvotes.

@ramsay \o

Loong

17:59

@pH13 $\mathrm pK_\mathrm a$

pH13

@Loong the a also? ... meh

I never did this ... why you start telling me now? !!table

Chemobot

(۶ૈ ᵒ̌ Дᵒ̌)۶ૈ=͟͟͞͞ ⌨

IͶΔ

!!untable

Chemobot

┻o(Ｔ＿Ｔ )ミ( ；＿；)o┯

Loong

@Chemobot is that a table?

ramsay

18:00

why everyone types !!table ?

Chemobot

(ノ｀Д´)ノ~┻━┻

IͶΔ

@ramsay Table flips are a tradition here.

@Ramsay: knowyourmeme.com/memes/flipping-tables

ramsay

oh, i see O-O

lol

pH13

@Loong also k_\mathrm{W} ?

Loong

@pH13 yes

pH13

18:03

grml

!!wiki/Besserwisser

Chemobot

Know-it-all

A know-it-all or know-all is a person who obnoxiously purports an expansive comprehension of a topic and/or situation when in reality, his/her comprehension is inaccurate or limited. This display may or may not be directly expressed. The German word Besserwisser is also used in some languages, literally meaning "better knower." == See also == Pedant Polymath Smart Alec Whiz Kid == References... ==

pH13

@Loong ;)

please keep doing that

Loong

;-)

Does it matter for your answer that pH is actually defined in terms of activity rather than concentration?

pH13

I guess for pkc<2...3, yes ... but as no teacher cares, I also didn't

I might want to note that as one assumption.

ramsay

is chemobot a bot?

pH13

18:12

@ramsay indeed

IͶΔ

Why does quickly cooling a saturated solution cause precipitation?

pH13

does it?

IͶΔ

It usually does.

pH13

stuff is better dissolved in hot solvents, why when cooling it, it's again not so good dissolved which follows in precipitation

!!wiki/Recrystallization_(chemistry)

Chemobot

Recrystallization (chemistry)

In chemistry, recrystallization is a technique used to purify chemicals. By dissolving both impurities and a compound in an appropriate solvent, either the desired compound or impurities can be coaxed out of solution, leaving the other behind. It is named for the crystals often formed when the compound precipitates out. Alternatively, recrystallization can refer to the natural growth of larger ice crystals at the expense of smaller ones. == ChemistryEdit == In chemistry, recrystallization is a procedure for purifying compounds. The most typical situation is that a desired "compound A" is ...

IͶΔ

18:18

Yes, but why does slowly cooling it sometimes make a supersaturated solution?

I mean, why the different results in the method of cooling?

What happens in quickly cooling that doesn't in slowly cooling?

Hippalectryon

Reorganisations. Isnt it just like how if you hit supercooled water it freezes, but if you lightly move it it stays liquid ?

IͶΔ

@Hippalectryon This does not provide an answer to the question. To request clarification from the author, leave a comment below their post.

I didn't mean supercooling.

Oh wait.

Hmm . . .

pH13

for me, your second question also sounded like supercooling

Ramanewbie

@hippa The bot on my RPi apparently can't display images. !!img/[] return error. Why ?

Chemobot

Ramanewbie

18:22

That error ^

Hippalectryon

I gtg :( sya

Ramanewbie

k

Brian

@IͶΔ Physical agitation/disruption. In order for crystals to form (or for gas bubbles to form, too, for that matter), there's sort of an "activation cluster size" that it has to get across.

IͶΔ

Oh

Brian

Lone dissolved ions/molecules are more stable than clusters of, say, four crystal units (no idea if that's the right number).

IͶΔ

18:24

To Googlez

Brian

But, once you get beyond some critical number of particles, it'll happen rapidly.

Alternatively, surfaces & edges & such can act as a 'catalyst' for nucleation

pH13

@Brian when reading this, I have to think about a fancy paper about very very very clean water that freezes way below 0 °C

Brian

Either way, you have to 'leapfrog' up to a large enough cluster size such that continuing to form a larger crystal/bubble is energetically favorable.

(I guess "Free-energetically favorable," to be precise)

IͶΔ

:o It all makes sense now

Brian

In theory, actually, both fast cooling and slow cooling should have the same potential for overcooling

But there's essentially always some physical disturbance associated with fast cooling that provides the 'bump' needed to get over the nucleation activation barrier

It's why in chem lab when you're boiling water for a hot water bath you're always supposed to scratch the beaker you're boiling in, or to add boiling chips.

Both provide nucleation sites that catalyze water vapor bubble formation.

</science rant>

IͶΔ

18:28

You changed my life

Thanks @Brian

Brian

<bows> My pleasure!

IͶΔ

There was a use to this chat after all . . . !!table

Chemobot

(ﾉ´□｀)ﾉ ┫:･’∵:.┻┻:･’.:┣∵･:. ┳┳

IͶΔ

OK I gotta move. See you all \o

Brian

I was tempted to !!table, but... is there such a thing as a "happy !!table"?

Chemobot

18:30

(ノ͡° ͜ʖ ͡°)ノ︵┻┻

Brian

That.... actually looks like one, yes.

IͶΔ

@Brian I was tempted to tell @Hipp to let us categorize table flips.

pH13

@Brian but that was just coincidence

IͶΔ

Here's an xkcd as a last message today:

Giving @Brian 4.5 stars

Brian

:-)

!!confetti

pH13

18:32

@Hipp feature-request

Brian

It would be a real mess if @Chemobot's cache ever got wiped -- would he re-scan the chat history, and then re-post every post he ever posted? That would be... massive output.

pH13

but funny

Brian

I can hear the groanings of the SE chat server now

pH13

@IͶΔ only 25 rep so far !!table ... moar! moar!! moar!!! ... moar(!)_n

Chemobot

(ﾉ｀□´)ﾉ⌒┻━┻

Loong

18:39

2

Brian

Uh. Wut?

Loong

is it already april 1st?

Brian

Oh. Maybe where @Mart is?

Just shy of 9pm UTC

2:40pm EDT here in Ohio

@pH13 Interesting -- is its freezing point actually depressed, or does it just have a huge capability for supercooling?

(I assume the latter)

Loong

note the date in the corner

pH13

@Brian link didn't work ... I'll try again tomorrow. It was in nature ... moore and someone else ... :D

Brian

18:53

Mmk. Yeah, ultraclean water in an ultrasmooth container should supercool a looooooong way.

pH13

19:05

was about -48 °C or so

@Loong there the activity comments come in ;)

Loong

@pH13 I have warned you

pH13

He must be wise to know what I think ;)

but then he has a phd

I am unsure if it's the error range or the pkc-scale that is bad ... or both?

Loong

19:31

@pH13 This report focusses on the measurement of pH. But maybe you can use it for another answer.

IͶΔ

20:42

@Loong Somewhere in the world

IͶΔ

20:59

The game is unsurprisingly entertaining.

Hippalectryon

21:26

@Brian There's no cache

@Ramanewbie What was the issue again ?

Ramanewbie

The bot is running on my RPi. All works fine, except that the !!img/[] command returns an error.

Chemobot

Ramanewbie

This error ^

I don't understand why, since everything else works fine.

Hippalectryon

what molec name did you try ?

Ramanewbie

@hippa any, such as water or cyclohexane.
At test-room (10121), your bot returns the image properly and not mine.

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