The Periodic Table

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1:59 AM

@MollyCooL That KS Verma pic you'd shared - postimg.org/image/nn1x91r31, I wonder if bromination (at the bottom) from the bromonium ion would involve a classical 3deg carbocation

it will most probably be a transient intermediate

i meant, the bromonium ion in alkenes used to be a non-classical carbocation

not sure here though

for cyclopropane

Tanuj

@GaurangTandon what's the answer to that rod question ? I also seem to be getting B

Gaurang Tandon

@Tanuj it's A

Tanuj

Yup , the other two don't make any sense

Tanuj

2:22 AM

@GaurangTandon how you convert a line in cartesian form to vector form (in 3d) ?

$$\dfrac{x-1}{4}=\dfrac{y-4}{0}=\dfrac{z-6}{-2}$$

user280247

3:15 AM

@hBy2Py I would like to study diatomic molecules very much like in szabo ostlund

hBy2Py

3:45 AM

Anybody interested in a focused partner-study of quantum chemistry fundamentals of diatomics, talk to @santimirandarp

2 hours later…

Akash. B

5:28 AM

How scientist create new elements?

Avnish Kabaj

5:39 AM

@Akash.B popsci.com/science/article/2013-04/making-new-elements

Akash. B

ohh

how water is formed? I have learned that the water is h2o but how is this possible ?oxygen exist has a molecule, am I right

Avnish Kabaj

@Akash.B you just need a spark/energy source to start the reaction between H2 O2

After that it's spontaneous I think

Gaurang Tandon

6:16 AM

@[any room owner] can we remove the two obsolete pins from mar14? the right sidebar is almost full as of now

thank you

@Tanuj take its original point as \vec a=(1,4,6); then take its direction ratios as \vec b = (4,0,-2), then simply do \vec r = \vec a + \lambda \vec b (\lambda is a parameter)

3 hours later…

Gaurang Tandon

9:22 AM

OMG

A: What are "tensides"

I don't remember to have seen the term tensid outside the context of the German language. The term is typically applied to agents that decrease the surface tension (hence tensid) of water. Note that the logic behind the English equivalent surfactant is just the same. So, in summary tensid and ...

Klaus is back!!

Yay!!!

4 hours later…

hBy2Py

1:21 PM

@GaurangTandon Yup. Done.

Gaurang Tandon

@hBy2Py thanks

and please remove the star on this

7 hours ago, by Gaurang Tandon

@[any room owner] can we remove the two obsolete pins from mar14? the right sidebar is almost full as of now

hBy2Py

Huh, I didn't know I could scrub stars as a room owner

Thought only mods could do that

Gaurang Tandon

@hBy2Py you can go on a streak and scrub all stars ;) anyway, thanks!

@hBy2Py the question you put a bounty on - aren't only weak acids plus their salts with strong base (or vc-vs) called "buffer solutions"?

or is this beyond high school stuff?

hBy2Py

@GaurangTandon That's my interest -- I'm wondering if it actually does serve as a pH buffer somehow, b/c I absolutely wouldn't expect it to.

Gaurang Tandon

oh isn't that "original research" and hence off-topic for SE? ;)

hBy2Py

1:32 PM

I wouldn't think so... OP talks about it like it's an established thing.

The thermodynamics of it are presumably well understood

but yeah, it's beyond-high-school thermo

Bounty Hunter

Q: How does the HCl-KCl Buffer work?

I have just been studying the $\ce{HCl}$-$\ce{KCl}$ 'buffer', but there are still quite a few things I am uncertain about. I would appreciate any help in clearing up some questions I have. What I understand (possibly incorrectly) from my research so far: Water is the weak acid acting as a buffe...

hBy2Py

possibly all the way into grad-school-thermo.

Good timing, @BountyHunter

Gaurang Tandon

@hBy2Py oh well :( i was hoping to grab that +50 like a low-hanging fruit; next time put your valuable rep on some easy questions ;)

hBy2Py

There's a deleted answer to the question, that links here, with little further detail in the answer.

And the link does talk about this sort of HCl/KCl system, but the actual thermodynamics of the description are lacking.

Gaurang Tandon

"The addition of an acidic compound to a strong acid solution, such as a hydrochloric acid (HCl) solution, increases the solution's hydrogen ion concentration"

this line? ---^

(on that webpage)

hBy2Py

2:05 PM

@GaurangTandon Not that line specifically, but yeah, the second half of the section that starts with that line.

Gaurang Tandon

2:36 PM

@hBy2Py alright! this is really interesting...

hBy2Py

2:57 PM

Best I can figure, it must be that increasing the ionic strength lowers the activity of H+ and/or Cl- enough that the pKa of HCl increases to something where it actually buffers in a practically useful range.

Pretty far to bring up the pKa, though... Wikipedia says it's -6.3 in dilute solution

Gaurang Tandon

tbh i've entirely no clue; you may really want to comment these interesting thoughts directly below the bountied question so interested answerers will have a head start

Gaurang Tandon

3:22 PM

@M.A.R.ಠ_ಠ Another gem I found today hidden in meta - data.stackexchange.com/chemistry/query/654396/…

MollyCooL

4:19 PM

@GaurangTandon I have no idea of what you are saying reg intermediate , all I get is that you’re referring to the image I shared and bromination mechanism