The Periodic Table

05:12

Can someone help me interpret the following comment? (It will be deleted, as there is a flag on it.)

Alright Martin, you know more than one of the most notorious analytical/environmental chemists in the world (lab/lecture instructor)... tough guy — camerobn 19 hours ago

TanMath

05:29

@Martin-マーチン it seems like a compliment and sarcasm at the same time...

Martin - マーチン

yeah it really confuses me O.o

TanMath

@Martin-マーチン maybe this camerobn is some famous scientist?

Martin - マーチン

judging from the question, he is just a student... but maybe his supervisor is some kind of a legend...

TanMath

@Martin-マーチン yes.. I realized that.. maybe so!

Is it even possible for the standard deviation to be zero?

Martin - マーチン

I have no idea...

that sounds like a mind bender

but i think no...

TanMath

05:37

@Martin-マーチン unless he got the exact same measurements (which is what he claims to say), which is virtually impossible..

Martin - マーチン

well even then, the standard deviation cannot be less than the accuracy of the measurment

and there is afaik no method with absolute precision

TanMath

@Martin-マーチン how come? the average and the trial measurement will subtract out to zero, and you are just adding a bunch of zeros and square rooting, giving you a zero!

@Martin-マーチン true.. but even by chance, it is virtually impossible... In reality, if it were to be measured w/ something more accurate, then almost certainly it would be different

Also, what is the point of the question? The standard deviation has the same amount of sig-figs as the trial sig-figs (i think.. depends on the values).. this question is really trivial...

Martin - マーチン

@TanMath I think this answer by @Loong explains it quite well

TanMath

@Martin-マーチン sig figs and uncertainty are different, aren't they? There are many ways to calculate uncertainty for sure..

Martin - マーチン

well, sig figs are a way to imply uncertainty

4

Q: Significant figures used to imply stated error?

The question reads, " express each of the following quantities using significant figures to imply the stated error". a)$2.3 \pm 0.001$ b)$1.989 \pm 0.0003$ I think the first one is 2.300 because the zero in the thousands place implies an error of $\pm 0.001$ but how do I use sig figs to imply...

notation

TanMath

05:52

@Martin-マーチン yes.. but the rules are different.. anyway, nice chatting with you, I need to leave.. see you tomorrow at the TRE!

Martin - マーチン

@TanMath Yes it was nice... have a great day! I won't be able to make it to the TRE, because a friend and I are celebrating his birthday.

Ϻ.Λ.Ʀ.

07:09

I won't be here in this TRE either. O.O

Maybe @Jan should be the leader™ this time.

@Martin-マーチン Sarcasm. Brutal in that.

Martin - マーチン

@Ϻ.Λ.Ʀ. so this is insulting then, right?

Ϻ.Λ.Ʀ.

@Martin-マーチン Yes.

Martin - マーチン

ಠ_ಠ

Ϻ.Λ.Ʀ.

Whee go and sting!

Martin - マーチン

i sometimes wonder, why even bother...

Ϻ.Λ.Ʀ.

07:16

Why even bother do what?

Martin - マーチン

08:03

to leave comments...

Ϻ.Λ.Ʀ.

Because you're a nice guy.

Martin - マーチン

I am not so sure about that any more...

Ϻ.Λ.Ʀ.

Take a deep breath. Look beyond the horizon and then, ~~think~~ realize that chem.SE wouldn't have been anything without you, and won't be anything without you.

orthocresol

09:31

0

Q: What are the major product(s) formed when cis-1-bromo-2-methylcyclohexane reacts with sodium isopropoxide in isopropanol?

What are the major product(s) formed when cis-1-bromo-2-methylcyclohexane reacts with sodium isopropoxide in isopropanol? I don't understand this question. I have tried putting I as the answer but that is not correct. I have also tried putting II as the answer and that's not correct as we...

organic-chemistry homework

I thought it would be option 1.

Martin - マーチン

I'd go with 1,2,3 and 4... lol

orthocresol

09:54

Yeah.. It is messy.

Martin - マーチン

well the question is basically, is isopropoxide a better nucleophile than base or not... I would guess not... ergo 1 and 2 should be the answer, because isopropoxide is kinda big also, but what do I know...

orthocresol

10:21

That's what I thought too, I thought it would be 1 because more substituted alkene, but I am not necessarily right either :p At first I thought the question was going to be about the bromine not having any antiperiplanar hydrogens for an E2, but it wasn't about that..

Ϻ.Λ.Ʀ.

13:22

Oh, I might be here for TRE anyway.

Wildcat

=^.^=

Ϻ.Λ.Ʀ.

\o @Wild kitty!

WYSIWYG

14:47

@ManishEarth Hi Manish. I just saw your script for mathjax formatting on stackapps. Very nice. Is it possible for you to make another one for html tags for subscripts/superscripts and the " " character? I would have done it if I knew JS.

Ϻ.Λ.Ʀ.

@WYSIWYG He's a bit busy these days, I think.

@Todd I think I won't be here for TRE.

Could you guys find a way to push it through? Just do the query for tags on the first page.

Mithoron

15:08

-2

Q: please show your work

50g of substance A having a percent compostion of 40% ca, 48%0, 12% c and a molar mass of 100g/mol react with a solution containing 40g of hydrochloric aid calculate A) the number of molecules of gas formed in the reaction B)the mass of salt obtained if the reaction yield for itis 82% C) if t...

homework stoichiometry

Oh that's a good one, irony ensues :D

Jan

15:21

@Ϻ.Λ.Ʀ. Rejected.

Todd Minehardt

15:36

@Ϻ.Λ.Ʀ. - you will be missed :)

hi @jan @Mithoron

pH13

16:23

how long does this retagging stuff take?

orthocresol

16:59

well, since nobody is around, I will just spend today's TRE digging up questions with high votes and editing them and the answers wherever necessary.

or maybe I will do that another day, very tired now

pH13

ok

Jan

17:26

@orthocresol You need your beauty-sealeep?

orthocresol

18:00

@Jan didn't sleep much last night :/ it's the end of the week so I just want to rest

`( _ • _ )´ zzz

TanMath

18:17

@Ϻ.Λ.Ʀ. no!!! don't leave us!

who is the new leader!

Jan

@TanMath 'tis anarchy.

TanMath

I shall be the new commander-in-chief! I am the king! :)

@Jan @pH13 @orthocresol @Loong @ToddMinehardt welcome aboard! let us start the retagging!

Can we start with "acid-base"?

@Mithoron you can join us too! (sorry about almost forgetting you!)

Jan

18:44

I think, you're doing your own anarchy @Tanarchymath.

TanMath

@Jan yeS

Do you want to help? @Jan ?

I am going to lengthen the TRE, as nobody is participating except me! I will wait for someobdy to participate...

orthocresol

That's no longer an anarchy, it's a self-proclaimed dictatorship. ಠ_ಠ

@TanMath Since we are done with the broadest tags, i.e. homework and o/i/p chem, the remaining tags are likely to be more specific in nature.

I don't think everything has to have more than one tag.

TanMath

@orthocresol ಠ_ಠ

@orthocresol what about acid-base? or "water", etc.?

orthocresol

Some deserve to be retagged, but not all.

TanMath

they are broad tags as well, but not as broad as the others..

orthocresol

18:56

For example, Dissenter's question on superacids

10

Q: Why is magic acid a superacid?

The above is a representation of magic acid. The left part is the acid; the right part is the solvent. Why would this combination make for a particularly good acid? The left part looks like a sulfuric acid derivative, except one of the oxygens has been replaced by an electronegative fluorine. ...

acid-base

The [[reaction]] tag is debatable, and [[reaction-mechanism]] shouldn't be there, there's no mechanism

TanMath

@orthocresol i put "reaction" and "reaction-mechanism" as the question is about the reaction of this acid that makes it so strong..

@orthocresol ok.. i agree..

@orthocresol trurh be told, i thought we had to retag all of them.. Now i will not retag all of them, only some..

orthocresol

Yeah, as I was saying, this is just what happens when we are done with the broadest tags of all

It is difficult to rationalise a question only having an organic-chemistry tag, because organic-chemistry is such a broad topic

But it is not difficult to have a question with only acid-base

I mean, if you really wanted, you can add inorganic-chemistry to it

TanMath

@orthocresol oh, correct!

so TRE is over?

orthocresol

I don't know, you're the dictator

:)

organic-chemistry

There, I keep on forgetting how to get the tags to show up.

TanMath

@orthocresol by my dictatorship, it is not over.. But i am a nice dictator, so share your opinions! ;)

Jan

19:11

I'm out. No real desire to do anything today.

TanMath

@Jan sad to hear.. goodbye!

Jan

I'll just be the protesting citizen on the sidelines who is then jailed by the almighty dictator Vladimir Xi Kim Lukashenko-Castro.

TanMath

@Jan even more sad to hear.. enjoy!

Jan

19:25

@DictatorMath, please remember to make substantial edits. In one of the posts you could have corrected the incorrect use of MathJax without \ce for equations. In another you could have typeset pKa better by using $\mathrm{p}K_\mathrm{a}$.

Ϻ.Λ.Ʀ.

@Jan I'm the almighty dictator Vladimir Xi Kim Lukashenko-Castro and I hereby arrest you for not leading TRE.

Jan

@Ϻ.Λ.Ʀ. I prefer that you would do my work for me D= I don't really have the spare time to lead the event at all. Sometimes I have it to help but that's it.

TanMath

@Ϻ.Λ.Ʀ. i tried my best! nobody listened!

@ReviewerJan As I am the dictator, I get to do what I want!
ಠ_ಠ

;)

Jan

19:41

@TanMath Rejected

Anarchy rules! I shall not subject myself to @Tantator!

TanMath

@Jan as the dictator, I reject you..

@Ϻ.Λ.Ʀ. codictator, let us do something about this @ReviewerJan protester!

Jan

Let's have a quick show of hands. In favour of @Tantator? Okay. Neutral towards the question? @Tantator's Tantatorship rejected by anarchistic democratic vote-of-hands.

TanMath

@Jan I didnt see any hands!

@Jan democracy doesn't work! boo for democracy!

@ReviewerJan has nothing to say?

Jan

@TanMath Course you don't 'cause none were raised in your favour ;p

TanMath

@Jan i didnt see any hands.. hands for me or hands against me...

@ReviewerJan still has nothing to say?

@Jan i am a successful dictator!

Jan

19:59

@TanMath I only asked pro you and neutral. Everyone else is against you ;p

The way a mayor gets the whole city council to conform with them ;)

TanMath

@Jan well, who is even here to put their hands up.. in fact, @orthocresol eould support me!

orthocresol

I support the revolution

The time has come

Les Miserables 10th Anniversary (HD) - Do You Hear the People Sing (18/41)

►

TanMath

@orthocresol you support who?

Jan

Anarchy!

orthocresol

DOWN WITH THE DICTATOR -----E

Jan

20:13

After my home hockey team threw away a 4:1 lead and will begin the third period with a 4:4 score, I think I'll go shopping and home. See ya, guys o/

orthocresol

Goodnight!

orthocresol

20:36

@Ϻ.Λ.Ʀ. I flagged because it doesn't answer the question.

The question is basically asking: In an SN1 reaction, is the cation rearrangement faster than the nucleophile attack

The answer is basically saying: "An SN1 doesn't involve simultaneous collision of three atoms".

I am sorry if I clicked VLQ, I believe I did flag for NAA.

OP obviously 1) knows the mechanism of the SN1 reaction and knows that it is not concerted, because he knows of the existence of a carbocation 2) knows that the SN2 exists.

So the answer is entirely off-base. It is not answering the question of whether the rearrangement occurs before it is intercepted by the nucleophile. It is just saying something entirely irrelevant to the question.

"So chemistry isn't just about doing overall mass balanced equations." OP isn't even trying to write a balanced equation, because this is about the mechanism, not stoichiometry.. "It is trying to show you how you got from point A to point B." The question he was asking is not "how do I get from point A to point B". It is: "Is it possible that there is an alternative path to point C?"

I am not against having more people answering questions. I am just against having more answers that are not answers. Still, if everybody believes it is actually an answer, then so be it.

Ϻ.Λ.Ʀ.

21:19

@orthocresol Oh. Then you have to give me time to read that answer. Tomorrow . . .

TanMath

@Ϻ.Λ.Ʀ. hello codictator!

@Ϻ.Λ.Ʀ. proper use of ellipsis! great! I still cant master that...

Ϻ.Λ.Ʀ.

@TanMath codictator needs some sleep . . .

TanMath

21:35

@Ϻ.Λ.Ʀ. but when @ReviewerJan revolted, where were you? if you go to sleep, the revolution will be too strong as there is no codictator to help! no!!!

@Ϻ.Λ.Ʀ. TanMath says "gud night!" @Tantator says "Wake up!" :/

Stack Exchange

22:10

0

Q: How to reduce the size of figures

How do you use markup to reduce the size of figures? I'm too lazy to download, reduce with some image editor and upload the pictures. See for example: Raney nickel as a reducer