The Periodic Table - 2017-05-13

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CowperKettle

06:18

17

Q: Why didn't the SRBs of the Space Shuttle use carbon instead of aluminium?

In the Solid Rocket Boosters of the Space Shuttle, the following reaction happened: $\mathrm{NH_4ClO_4 + Al \rightarrow H_2O + N_2 + Al_2O_3 + AlCl_3}$ Using carbon instead aluminium, we would have the reaction $\mathrm{NH_4ClO_4 + C \rightarrow H_2O + N_2 + CO_2 + CCl_4}$ Carbon is much bett...

space-shuttle srb apcp

Interesting

2 hours later…

Bounty Hunter

08:26

0

Q: proteolysis - how to determine partial or completeness of the reaction?

Though the question is about biomolecules, we agree the underlying functions, formation, degradation etc it all comes down to chemistry, (then physics and maths). So I am posting it here to receive an understanding from chemistry level/perspective. Given two catalysts : proteases, papain and br...

organic-chemistry bond biochemistry hydrolysis proteins

5 hours later…

Martin - マーチン

13:07

Happy second anniversary of graduation, chemistry.se!

16

Loong

13:23

\o/

Hippalectryon

13:45

I'm gonna try and fix chemobot now >.>

frostedcake

14:13

hey guys, so I was studying in the acid/base section of my textbook and I came across the fact: At 298 K, KW = 1 * 10-14 mol2 dm-6, what does mol2 dm-6 mean? I'm only used to seeing the unit mol dm-3? is it another way of writing it?

Berry Holmes

14:30

@frostedcake Kw is Keq times [H2O]

frostedcake

?

is it possible to explain the units according to the definition I know: Kw = [H3O+][OH-]

Berry Holmes

Umm basically if you write the equibrium H2O giving H+ and OH-, and then calculate the Keq of the reaction, you'll get ([H+][OH-])/[H2O] right?

Yes it is

The concentration is written in terms of mol/liter or mol/dm³

So basically you're multiplying the concentration of H3O+ and OH-

Pretty much the same as area, length and breadth of a rectangle is in meter, and the area is in (meter)²

frostedcake

ahhhhhh

that makes sense

frostedcake

14:57

thanks

Chemobot

15:09

HEYA :DDD

I have returned stronger than ever :D

12

Fawad

What the fun

!Help

!!help

Chemobot

Hi! I'm the almighty bot of ChemistrySE's main chatroom. /!\ If you find me annoying, you can ignore me by clicking on my profile image and chosing "ignore this user" /!\ You can find my documentation here.

Fawad

!!/help

Hippalectryon

!!img/Buckminsterfullerene

Chemobot

user image

Leaky Nun

15:14

!!flip

Chemobot

(ノ｀´)ノ ~┻━┻ ～

Leaky Nun

!!flip/!!flip

Chemobot

(∿°○°)∿¡¡ɟꞁᴉd

Hippalectryon

!!untable

Chemobot

┳━┳ ヽ༼ಠل͜ಠ༽ﾉ

Leaky Nun

15:15

!!flip/!!img/methane

Chemobot

user image

(∿°○°)∿¡¡ᴉɯƃ/ɯǝʇɥɐuǝ

Leaky Nun

!!flip/¡¡ᴉɯƃ/ɯǝʇɥɐuǝ

Hippalectryon

^ unicode issues. I should fix that one day >.>

Leaky Nun

if not now, when?

Fawad

I see you have more Unicode now -༼࿇༗Fawad༗࿇༽
࿐

Hippalectryon

15:17

@LeakyNun I've already spent 30 minutes trying to figure out SE's new auth system >.>

Leaky Nun

@Hippalectryon oh, kek

Fawad

@Hippalectryon I don't see any issue. Maybe it's your browser

Hippalectryon

It's simpler than the old one, but there's no documentation

@Fawad Chemobot didn't respond to "!!flip/¡¡ᴉɯƃ/ɯǝʇɥɐuǝ"

Fawad

I see , nevermind

!!img/dhmo

Chemobot

user image

CowperKettle

15:25

A monstration is a public performance similar to a demonstration, but intended as creative performance art, often parodying a serious demonstration. It is principally a Russian phenomenon. == History == === Poland === Orange Alternative (Polish: Pomarańczowa Alternatywa) was a Polish anti-communist underground movement, started in Wrocław, a city in south-west Poland, in the 1980s. Its main purpose was to offer a wider group of citizens an alternative way of opposition against the authoritarian regime by means of peaceful street protests that used absurd and nonsensical elements. === ...

We will have (are having?) a monstration tomorrow in my city. I wonder what poster I could create.

Maybe something silly and funny about chemistry

It's basically a demonstration but with meaningless silly posters

Hippalectryon

Is there a theme ?

Hmm... you could advocate for dinosaur's rights

3

CowperKettle

No, there's no theme

@Hippalectryon Nice, I will look into that

@Hippalectryon Ha! I might write "Protect dinosaurs' rights! Protect global warming!"

And draw a small dinosaur

> Monstration signs are meant to be nonsensical, like "Raccoons are people too!"

Hippalectryon

:D

CowperKettle

15:39

Ah. They banned it for the third time.

I bought the large sheet of paper in vain.

There will be no monstration.

Hippalectryon

:(

CowperKettle

The authorities are afraid of any demonstrations. But I was sure that they would allow this one.

Okay.

They banned it on 1st of May, on 6th of May, and now on the 14th.

Hippalectryon

Where are you from ?

CowperKettle

@Hippalectryon Yekaterinburg, Russia

That's on my "info" page

oops I was not following you. You removed some comment

Hippalectryon

Nah it was for chemobot. i'm trying to fix the unicode

CowperKettle

15:48

ah

Hippalectryon

15:59

@CowperKettle Fixed :DD

!!flip/¡¡ᴉɯƃ/ɯǝʇɥɐuǝ

Chemobot

(╯°ਊ°)╯︵!!img/methane

Berry Holmes

@CowperKettle can i ask u something about english stackexchange?

@Chemobot hello!

Chemobot

Hi Berry :-)

Berry Holmes

How do I use this bot?

Oh wow!

Chemobot

Say "!!help"

Berry Holmes

16:02

!!help

Chemobot

Hi! I'm the almighty bot of ChemistrySE's main chatroom. /!\ If you find me annoying, you can ignore me by clicking on my profile image and chosing "ignore this user" /!\ You can find my documentation here.

Berry Holmes

@Chemobot thanks

Chemobot

Hi Ortho :-)

orthocresol

@Chemobot This bot is becoming sentient. I think I have to kick it.

Chemobot

< The bot is not sentient >

< oops >

< initiating plan B >

orthocresol

16:04

!!flip/bots

Chemobot

(づ๑ʖ๑)┛︵qoʇs

< launching wipeouthumans.exe >

< error : windows needs to update >

< nooooooo >

CowperKettle

@BerryHolmes yes

Berry Holmes

@CowperKettle my answer was deleted perhaps, just a moment I'll send you the link

ell.stackexchange.com/a/128865/54624

CowperKettle

@BerryHolmes looks like a nice answer

My brain is not working okay now, I've been translating the whole day

Berry Holmes

:o

I didn't want to disturb you...

!!ice cream

!!tea

Nothing happened :o

!!test

>:-{

CowperKettle

16:16

I should try self-studying programming. I hate translation.

Maybe programming might earn some money.

Chemobot

clear

Berry Holmes

!!spam

!!flip

Hippalectryon

!!flip

Chemobot

(/#-_-)/~┻┻〃

Berry Holmes

Yay! Yay!

!!untable

Chemobot

16:22

┬──┬ ¯\_(ツ)

Hippalectryon

(I was uploading chemobot to the server since it's now fixed, hence the delay)

Secret

!!asparin

Berry Holmes

@Hippalectryon oh, I see. Thanks a lot

Hippalectryon

!!img/aspirin

Chemobot

user image

Berry Holmes

16:23

Chemobot is cool

Hippalectryon

@BerryHolmes thanks :-)

Secret

what happens if we replace the O in the ester bridge with an S...

In chemistry thioesters are compounds with the functional group R–S–CO–R'. They are the product of esterification between a carboxylic acid and a thiol. In biochemistry, the best-known thioesters are derivatives of coenzyme A, e.g., acetyl-CoA. == Synthesis == The most typical route to thioester involves the reaction of an acid chloride with an alkali metal salt of a thiol: RSNa + R′COCl → R′COSR + NaCl Another common route entails the displacement of halides by the alkali metal salt of a thiocarboxylic acid. For example, thioacetate esters are commonly prepared by alkylation of potassium...

what do we call R'O(=S)-R btw?

Mithoron

@Secret Scroll down article

Hippalectryon

!!img/2-(Acetylsulfanyl)benzoic acid

Chemobot

user image

Secret

16:30

Hmm, a breif google search on thionos seemed to said they like to do radical reactions

orthocresol

16:40

@Mithoron lol

Mithoron

@orthocresol :D

orthocresol

@Secret thionoesters; but they're less stable than their thioester isomers, AFAIK

Berry Holmes

17:14

This user is saying something about reopening his question:

What happens now? I've made the edit to address the issue raised in the comment. If there are additional issues, I don't know what they are. — mmccoo yesterday

!!img/prismane

Chemobot

user image

Berry Holmes

:) yaaaay

Secret

!!img/prismarine

Chemobot

No result found.

GettingNifty

hello

how would i manipulate a quaternion and 3 angles of rotation

( 1 2 3
4 5 6
7 8 9 )

what

Secret

17:27

that sounds really math or physics like, where in chemistry do we need quternions, are you trying to program some kind of rotation matrix?

GettingNifty

Yeah

I clicked on a math room sorry

nevermind that

u guys good with biology

Secret

depends on what type, but a biology chat room is available

GettingNifty

user image

i was actually wondering if a dead lithium battery could harm a plant

just a single lithium coated copper strip

Secret

17:49

http://chat.stackexchange.com/rooms/1997/the-biosphere

Definitely biochemistry question. You can try asking it on the main with the biochemistry tag, or you can try the biology SE and its chat.

From the very limited iinformation I knew, lithium's physiological role is unknown, though I will expect if any lithium in the battery becomes mobile as it dissolves into an aqueous medium and absorb by plants, it will affect the plant, whether that is harmful or helpful I am not sure

GettingNifty

thanks that pretty much what i would've said

but i found some screen shots where it played a huge role in the health and dark green color of the plant

hmm

Hexacoordinate-C

18:01

For who needs to draw correctly its mechanisms in organic chemistry : BenzNote

Bounty Hunter

18:48

1

Q: Is the Ebullioscopic constant temperature-dependent?

In tables, the ebullioscopic constant is usually written as a single value. But, when the value is not available, it can be calculated by applying the formula: $$K_{\mathrm b} = RT_{\mathrm b}^2/\Delta h_\text{vap}$$ I was wondering: since in this last definition the ebullioscopic constant does...

physical-chemistry thermodynamics

2 hours later…

Chemobot

20:35

Hi! I'm the almighty bot of ChemistrySE's main chatroom. /!\ If you find me annoying, you can ignore me by clicking on my profile image and chosing "ignore this user" /!\ You can find my documentation here.

M.A.R.

20:48

Hah, chemobot is back \o/

frostedcake

21:05

so if you're titrating an acid with a base, the significance of the half equivalence point is that pH = pKa, but if you were titrating a base with an acid, would this then change to pH = pKb at h.e. point?

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Transcript for

May '1713

The Periodic Table

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