The Periodic Table

user228700

4:03 AM

Hi everyone :-)

user228700

My textbook says " $BF_4^-$ ions have very low tendency to form complexes in aqueous solutions."

user228700

Does anybody know why..?

user228700

My textbook also says "The greater the size of the terminal atom, the greater is the bond angle". I keep picturing the ball and stick model in my head to make sense of this statement. Is this an OK way to think about this or is there a better, more correct reasoning?

user228700

4:20 AM

Also, is anybody able to explain why the bond angle tends to decrease with increase in p-character (according to Bent's rule)

user228700

(Eg: $OF_2$ vs. $OCl_2$)

user228700

4:33 AM

Aalso, (sorry :-P) my textbook says that the more polar a bond gets, the shorter it becomes. Why is this..?

user228700

4:53 AM

@BernardMeurer: Hi :-) I read that u were confused about drawing MO diagrams. If u're still confused, I recommend watching this:

user228700

14. Molecular orbital theory

►

user228700

She's absolutely wonderful :-) (From MIT OCW)

Martin - マーチン

5:23 AM

@hBy2Py thanks. i'll look into it :D

user228700

@Martin-マーチン: Hi :-)

Martin - マーチン

o/

Martin - マーチン

5:46 AM

@hBy2Py A functional that is hated by almost 20% of the participants should not be on #3...

did you take part in the survey?

M.A.R.

7:57 AM

in Language Overflow, 10 mins ago, by CowperKettle

@Dis welcome back

@Zhe Welcome to our humble chat

DHMO

8:14 AM

@Kaumudi How is the p character different in OF2 and Cl2O?

user228700

@DHMO Bent's rule.

DHMO

@Kaumudi tetrahedral perfect symmetry?

user228700

@DHMO Hm, perhaps...

user228700

@M.A.R.: Is that u, Rubisco?

M.A.R.

Is that me?

Who knows.

user228700

8:16 AM

OK :-P

DHMO

@Kaumudi so in OF2, F has more p character? and in Cl2O, O has more p character?

user228700

No, no! I'll get back to u.

DHMO

@Kaumudi My proposal: increase in p character -> more diffuse -> less repulsion -> less bond angle

M.A.R.

8:43 AM

in Language Overflow, 8 mins ago, by CowperKettle

Lost in translation stuff are awesome

DHMO

9:57 AM

is there phenol anhydride?

M.A.R.

@DHMO Huh

DHMO

@M.A.R. you know, phenol is a weak acid

M.A.R.

Yeah.

What does that have to do with anhydride-ness?

You mean since it's an acid there could be an anhydride version?

Hahahahaha no.

orthocresol

Hmph.

@Martin-マーチン What you said sounds like what @M.A.R. plans to do. Which is fine, but presumably that means that my post is not going to be an absolute newcomer's post anymore.

Martin - マーチン

yeah....

M.A.R.

10:09 AM

@orthocresol What did he say?

@Martin-マーチン What did you say?

orthocresol

The comments on the answer haha

M.A.R.

Other than 'yeahWRONGELLIPSIS'

@orthocresol Oh. I read those, but I didn't try to decipher what I read.

I just read.

Martin - マーチン

@M.A.R. phenol + phenol -water = diphenyl ether

M.A.R.

@Martin-マーチン It's not called phenol anhydride is it.

You can't get a water out of one phenol.

DHMO

@M.A.R. you cant produce acetic anhydride from acetic acid either

M.A.R.

10:13 AM

In the end, you get the water out though.

Martin - マーチン

yeah one water from two acetic acids...

DHMO

i'm thoroughly confused.

what is the truth?

M.A.R.

Calling it phenol anhydride is like calling four 'three plus one' because 3+1=4. Don't do it.

orthocresol

At this rate, we should just defer this until you've proposed your new-user-mega-guide.

Sorry for non sequitur.

M.A.R.

@orthocresol Hell, that's gonna be some MONTHS ahead

We have to first settle the closure policy thing.

Today I'll write a meta post about 'policy on AMIRITE questions'.

orthocresol

10:16 AM

@M.A.R. Yeah. I know.

Martin - マーチン

@DHMO phenols are their own substance class, as are acids, as are anhydride

orthocresol

This is just irritating because we have a different vision of how to go about doing this.

And I can't do what I want if what you want is not concrete and discuss-able.

M.A.R.

@orthocresol We have a user called rene that eats ice cream whenever he disagrees with someone. Let's just eat ice cream

Martin - マーチン

@DHMO phenol can't form an anhydride because it would be an ether - i was just joking around

orthocresol

!!icecream

I'm not upset or anything, don't worry.

Chemobot doesn't give out icecream anymore?

DHMO

10:18 AM

M.A.R.

Hello not upset or anything. I'm MAR

Martin - マーチン

@M.A.R. months? havn't you been rambling for almost a year about that now?

DHMO

What is the name of the largest intermediate?

M.A.R.

@Martin-マーチン I have?

Well, we have plans for the future Mart.

I can't just throw stuff at meta.

Martin - マーチン

!!beer

Chemobot

10:19 AM

Martin - マーチン

@orthocresol He has priorities...

orthocresol

:D

M.A.R.

16 hours ago, by M.A.R.

MAR OK, you've gotta explain what you're planning to do.

50 mins ago, 42 minutes total – 52 messages, 3 users, 0 stars

Bookmarked just now by M.A.R.

Those aren't ordered though.

orthocresol

Yeah, not at all.

M.A.R.

I just have this mental ~~dis~~ order thing

orthocresol

10:20 AM

That's huge.

M.A.R.

@Martin-マーチン ಠ_ಠ

orthocresol

You see, I thought that we could just rewrite (or replace) one single post and be done with this issue for the time being.

Martin - マーチン

@M.A.R. ಠ_ಠ

@M.A.R. you have

DHMO

Why exactly is clockwise the right hand and counter-clockwise the left hand?

Martin - マーチン

Aug 7 '15 at 6:59, by inɒzɘmɒЯ.A.M

@Martin after I close my drama show on meta I wanna write the all-in-one new-user guide.

M.A.R.

10:22 AM

@orthocresol It's not an issue yet. It would be a real problem if we had users who really wanted to format things but couldn't learn a thing from the tutorial.

@Martin-マーチン Now you know my seekrit. That I am the MASTER PROCRASTINATOR

The ones that don't format currently are the ones that don't care to format, or read.

That's partly SE's tough navigation's part, partly because users of this site aren't expected to be good at web stuff, and partly no one's fault.

Martin - マーチン

And i remember something about the uber-answer crushing the character limit...

M.A.R.

@Martin-マーチン You gonna bring this up again . . .

He's searching for my chat messages now.

Yep. He's searching alright.

Martin - マーチン

@orthocresol It's a good start, and I really think we should do it

it needs to be shorter

and more descriptive

and less demanding

M.A.R.

And more ideal

Like the homework fairy

Martin - マーチン

@M.A.R. nah. your answer...

orthocresol

10:25 AM

@Martin-マーチン I'll get round to it in a while. Need to pop out for 20 min

Martin - マーチン

Take your time, there really is no need to rush

M.A.R.

@Martin-マーチン I first need to ask two good questions in two separate days to get that inquisitive badge.

And nothing rings a bell.

Martin - マーチン

uiuiuiui... inquisitive heh. going for the silver heh...

M.A.R.

What should I have gone for?

orthocresol

@Martin-マーチン Ok, in that case I will just post a chat message stating my intent to do so and link to it again in chat more than one year later.

Martin - マーチン

10:30 AM

@M.A.R. I want it, too, but... I need 17 more 0.o

@orthocresol hahaha....

noooooo

M.A.R.

@orthocresol You're starting to finally learn the ropes.

Snarky jokes aside, that message from 2015 was inspired by a all-in-one user guide, which was in either Movies or Parenting, don't recall correctly, and it was more like a food for thought, than a call for real action.

I also have a marginally real life that I have to attend.

16 hours ago, by hBy2Py

Ugh. Yeah, entrance exams are the worst.

orthocresol

@M.A.R. Is your life mostly imaginary?

M.A.R.

@orthocresol Mhm

orthocresol

Sometimes I feel mine is.

Martin - マーチン

my life is called netflix ;)

M.A.R.

10:36 AM

Everyone's is.

Martin - マーチン

10:46 AM

all joking aside... the idea ina put out there a year ago isn't something new. but things like that take time... quite a bit i guess... baby steps. I think an overhaul of the MJ page could be very helpful, because maybe then some more people will read it, understand it, use it.

orthocresol

@M.A.R. Before you embark on your amirite post

You want that to come under the custom off-topic reasons, amirite?

Martin - マーチン

i thought that would more or less be an amendment to the hw policy

M.A.R.

@orthocresol If people decide to close it.

There are a lot of possibilities.

One of which is adding it to the third slot.

orthocresol

Yeah, I thought it would come under HW

Feels like a waste of a slot

The third slot could be used for something much better

Such as "all questions by M.A.R. are off-topic"

M.A.R.

I LOVE IT

Why isn't it a reason already?

Martin - マーチン

10:54 AM

too few cases it could be used

also...

M.A.R.

We might even not close them

Martin - マーチン

the med reason needs an overhaul, too.

M.A.R.

But instead add the possible answer as an answer and be done with it

We'll see what meta decides.

Martin - マーチン

whot?

M.A.R.

@Martin-マーチン Yeah, it's not used a lot at all. I guess custom OT reason would've done the job.

@Martin-マーチン Well, why would we want to close AMIRITE questions? Because the answer would be VLQ, just a 'yes'.

Martin - マーチン

10:56 AM

well, that's not what i mean

M.A.R.

It's not important what you mean. It's important what words we put in your mouth.

Martin - マーチン

i like having the medical close reason, i just think there should be more guidance

@M.A.R. that's disgusting

M.A.R.

Thanks

@Martin-マーチン Well there should, but I don't like the medical reason's low number of uses

Martin - マーチン

do you need the reason for something else?

M.A.R.

No

But you guys want an empty slot

And AMIRITE might fill one slot.

It certainly comes up more often than medical

Martin - マーチン

11:02 AM

not according to the statistics, and I would not be so sure to have consensus on closing these questions in the first place

M.A.R.

@Martin-マーチン Eh, darn

Wait, how do you gather stats on AMIRITE questions?

Martin - マーチン

in the last 90 days, we have either closed the amirite questions as hw or there was only one, at least 12 were closed with med

@M.A.R. 10k tools has a table with the close statistics

M.A.R.

@Martin-マーチン We don't close AMIRITE stuff last I checked.

@Martin-マーチン I know, but we don't close AMIRITE.

That is, if it doesn't fit other reasons.

I'm saying this based on my feelings Mart. I've seen way more AMIRITE than med questions.

Martin - マーチン

chemistry.stackexchange.com/tools/question-close-stats (cc @orthocresol, nice toy :D)

regarding amirite:

16

Q: What should be done with "Is my calculation correct ?"-type questions?

I see many questions where the OP just asks whether his or her calculation is correct . These type of questions will most likely not be helpful to the majority . The questions pertain to a specific numerical calculation or to a specific application of a formula which the OP thinks might be wrong ...

discussion

M.A.R.

11:17 AM

@Martin-マーチン Yah I remember that

Martin - マーチン

and also

13

Q: "Is my calculation correct" is back again

The answers of What should be done with "Is my calculation correct ?"-type questions? clear out that questions need not be deleted by the OP/Community. Note: This is the Part-2 of the same issue but instead of editing it, I am starting this new thread so that the comments,answers and votes on ...

discussion unanswered-questions

I don't see the consensus coming that amirite questions will be closed...

Ashish Ahuja ツ

Hiya!

Martin - マーチン

if you make a meta post about that and the community decides to close these questions, then we can discuss a new close reason, before that... ther is no need....

M.A.R.

@Martin-マーチン Well of course. What else would the process look like?

@AshishAhujaツ \o

Martin - マーチン

@AshishAhujaツ \o/

I don't know... you were saying something about the close reason...

meh... maybe just a misunderstanding... well, we'll see

I've got to go... need to pack for my trip

M.A.R.

11:22 AM

@Martin-マーチン I was saying that the meta post will decide everything. One of the possibilities is that we'll end up closing them, and one of the ways of doing that is a custom slot.

Martin - マーチン

k - i understand

M.A.R.

┗[© ©]┛ ︵ ┻━┻

!!flip/Some people

Chemobot

(づಥਊಥ)づ︵Soɯǝ dǝodꞁǝ

user228700

11:45 AM

@Martin-マーチン: You're going away on a trip?! :-o

user228700

I've a quick question. When writing the condensed structure of organic compounds, is it necessary to keep the order of the smaller components?

user228700

ie. If there are two hydroxyl groups on either end of the compound, is it OK to write it as $(OH)_2$ at the end or something? For that matter, am I allowed to write it anywhere? It seems like that sort of ruins the whole point...

user228700

Yoohoo, anybody..?

DHMO

@Kaumudi For example?

user228700

BB in a little bit, sorry.

DHMO

11:59 AM

are you planning to write glycerol as CH2CHCH2(OH)3

kind of pointless

C3H8O3 is molecular formula

CH2CHCH2(OH)3 is kind of pointless

and misleading

condensed structural formula is supposed to represent the structure

Martin - マーチン

@Kaumudi conference and a bit of sightseeing beforehand snk-travel.com/isco2016/index.html

@Kaumudi it might be okay, for example for hydrates $$\ce{Me2CO + H2O <=> Me2C(OH)2}$$ other than that, rather abbreviate it with R and make clear what R stands for

DHMO

12:17 PM

@Martin-マーチン but aren't the two hydroxy groups on the same carbon?

Martin - マーチン

yeah... i might have misread the question... well...

hBy2Py

1:12 PM

@Martin-マーチン No, I've never participated -- I haven't felt like I really know well enough what I'm doing to have useful input.

How can I see which questions are contributing toward tag badges?

orthocresol

@hBy2Py Probably the fastest way is to simply search for your posts with the tag.

There's probably a SEDE query somewhere.

But say if I was looking for my answers under reaction-mechanism, I would search user:16683 [reaction-mechanism] is:answer

@hBy2Py data.stackexchange.com/chemistry/query/785/… (Oops, my bad. This lets you see the score, but doesn't list the questions. In any case, all answers to questions with the tag will contribute: so the simple search query works perfectly.)

user228700

@DHMO Wasn't planning on it, but that's what my book's gone and done, look:

user228700

DHMO

@Kaumudi no, your book done nothing wrong

user228700

1:24 PM

@DHMO That was my understanding as well. I'm confused now, because of my infamously useless textbook.

user228700

Ah, so it's OK when there's only one carbon in the middle?

DHMO

the principle is that groups around the same carbon are not to be separated

so HOCH(CN)2 is perfectly understood

(CN is a group)

user228700

Alright. Like I said, I'm turning blind so excuse me.

DHMO

@Kaumudi it's ok when theres however many carbons in the middle

@Kaumudi you are excused

in the name of our almighty seal

user228700

@DHMO No, not if the groups are on different carbons.

user228700

1:26 PM

Although the example I used was incorrect, at least I learned something!

DHMO

@Kaumudi glad to know

@Kaumudi that is correct

user228700

Thanks :-) Is anybody free to discuss bond angles and bond lengths?

DHMO

@Kaumudi still the OF2 vs Cl2O?

user228700

Well, sort of.

user228700

What happens is that I think I know why something is the way it is, and then I eff up in exams 'cause misconceptions aah!

user228700

1:28 PM

Exams, homework etc.

DHMO

I see

user228700

So I just wanna make sure I've got this right.

DHMO

Let's see if the mighty seal is kind enough to help you

@orthocresol

orthocresol

Bit busy.

Sorry.

DHMO

let's take that as a no

(i'm just kidding)

orthocresol

1:30 PM

Yes it is a no.

user228700

That's alright :-) @DHMO: Would u be so kind?

DHMO

@Kaumudi dartmouth.edu/~genchem/0102/spring/6winn/VSEPR2.html

user228700

Well, I don't exactly want to learn everything anew, like I just said.

DHMO

then what is your question?

user228700

I only want to discuss a few points that have been mentioned in my textbook under "Rules"

DHMO

1:31 PM

@Kaumudi sure, what are the points?

user228700

Warning: Please bear with me as I become the dumbest self I can be.

DHMO

@Kaumudi noted

user228700

Firstly, I must say that for some of these points, I'm keeping the ball and stick model in mind.

1,3-feeds

0

Q: Again, another correct answer downvoted and a wrong answer upvoted

The answer is this one: http://chemistry.stackexchange.com/a/61302/34047 Regardless of the effort I put into improving it is being downvoted, mine answer is correct (I studied metallurgy), while the other answer is wrong, clearly. Seems this problem is much more common, I see much more correct ...

discussion

DHMO

@Kaumudi noted

user228700

1:34 PM

OK, the first rule is that as the size of the atoms increase, the bond length increases.

user228700

This makes perfect sense when keeping aforementioned model in mind.

user228700

Plus, as the size increases and the electron clouds get closer, the repulsion b/w the atoms in question increases and hence, to counteract this, they move farther apart, thereby increasing bond length.

user228700

Does this make sense?

hBy2Py

@orthocresol Follow-on questions -- are there any tutorials for SE search (as in, what "id:xxx" things are available) and/or for these post lookup queries (SEDE, I guess?) that you and @Mart and all put together?

DHMO

@Kaumudi yes

user228700

1:37 PM

OK! Moving on to the next point...

user228700

Multiplicity decreases bond length.

DHMO

@Kaumudi does this mean "double bonds are shorter than single bonds"?

user228700

Yes, mine is just a pretentious way of saying that. Well, my textbook.

orthocresol

@hBy2Py If you perform any random search, at the right-hand side of the search results, there is an "advanced search tips" button.

user228700

Now, I'm not 100% sure of what I'm about to say, but I think that this is due to the overlap of even more atomic orbitals, bringing the two nuclei a little bit closer. I really doubt if this is correct tho.

DHMO

1:40 PM

@Kaumudi the shortened length is due to the increased bond dissociation energy

you can treat it as a stronger force

bringing the equilibrium position closer

user228700

Idk if that's the best way to describe it, hmm...

orthocresol

@hBy2Py for the SEDE (short for SE Data Explorer) queries, check out data.stackexchange.com/help, there is a tutorial somewhere on the page. I am sure you will understand it better than I do - I have zero knowledge of SQL.

DHMO

@Kaumudi bond lengths are just equilibrium positions

user228700

Can u elaborate on that, please?

orthocresol

Most of the time, I just use queries that other people have constructed, those are publicly available and can be searched for.

DHMO

1:43 PM

@Kaumudi the bonds are pulling the nucleus while the nucleus is repelling the nucleus

user228700

Yes, OK. Thinking...

DHMO

combined with other factors such as the other bond pairs, you have an equilibrium position

user228700

Yes, I didn't understand what u meant when u phrased it that way at first. I'm thinking about what u said before...

DHMO

user228700

When we introduce the $\pi$ electrons b/w the two nuclei, thereby forming a bond, this equilibrium shifts to a position in which the two atoms are closer together due to increased attractions b/w the newly introduced electrons and the two nuclei (the attractions outweigh the repulsions, yet again)

DHMO

1:47 PM

@Kaumudi ^

@Kaumudi yes

user228700

@DHMO Omg dude, I know! I was just thinking about what u said about bond dissociation energy...

DHMO

@Kaumudi sorry.

user228700

Thanks anyway :-) NP.

user228700

Just one second, let me figure that out...

user228700

I don't think that it is correct for us to think that the shortened length is due to the increased bond dissociation energy.

DHMO

1:50 PM

@Kaumudi you are absolutely correct

user228700

The shortened length is due to increased attractive force, which then causes the increased bond dissociation energy.

DHMO

@Kaumudi you are absolutely correct

user228700

:-P OK, I'm glad we agree.

user228700

Next point?

DHMO

@Kaumudi which causes the bond length to decrease

user228700

1:52 PM

Huh? No, I meant, can we move on to the next point..?

DHMO

absolutely

user228700

OK :-) As the difference in electronegativity increases, the bond length decreases.

user228700

Now this, I have to think about...

user228700

(I did think about it before, but I didn't get anywhere worth being :/)

user228700

OK, I have a theory.

user228700

1:56 PM

As the difference in electronegativity increases, the polarity of the bond increases, since the electrons tend to spend more time hanging around the more electronegative atom's nucleus.

user228700

This polarity induces partial charges on the participating atoms; a partial negative charge on the more electronegative atom and a partial positive charge (equal in magnitude, of course) on the less electronegative atom.

user228700

Oh, hang on...

MAR OK, you've gotta explain what you're planning to do.

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