Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
 Pages:  1  ..  8    10  
Author: Subject: Everyday Chemistry (provisional)
karlos³
International Hazard
*****




Posts: 1409
Registered: 10-1-2011
Location: yes!
Member Is Offline

Mood: aminoketonologisch 8)

[*] posted on 30-1-2021 at 18:04


My stirrers heating broke down(loose contact) and I tried to fix it...without being good or even skilled with technic stuff but more like my hands growing out of my ass, and the inevitable happened, I failed to put it together and don't want to try it myself in the fear of irreversible damaging it.

But I had a reaction to run, a ring closure/amidation for thalidomide, and simply tried it on the hotplate with four little stirbars as sort of boiling chips and as a help when swirling manually.
Worked as expected, surprisingly, even slightly better than the last time!

Encouraged by this, I spontanously made an experiment under the same conditions, except with oleic acid as substrate, to produce oleamide.
Worked fine too!

That felt a bit archaic, observing everything with hawkeyes throughout the reaction(only 45min each), but I am proud to be able to improvise , with insufficient equipment and all, and that without being affected negatively, or even at all by this drawback :)

But I already look forward to get back to my the pet-project(s) when a stirrer is on hand... those two amidations were just a poor substitute for it, but at least I could still do a little bit of the simple lab work.
View user's profile View All Posts By User
arkoma
Forum Redneck
*****




Posts: 1525
Registered: 3-2-2014
Location: Lago de Chapala, el lado norte
Member Is Offline

Mood: Nahua

[*] posted on 1-2-2021 at 13:16


fractional distillation of EtOH. notice the SM patch......



2021-02-01-151249.jpg - 67kB




Quote:
Travel is fatal to prejudice, bigotry, and narrow-mindedness, and many of our people need it sorely on these accounts.

Mark Twain


Smash. All. Icons
View user's profile View All Posts By User
ChemTalk
Hazard to Self
**




Posts: 64
Registered: 13-12-2018
Location: United States
Member Is Offline

Mood: colloidal

[*] posted on 1-2-2021 at 14:24


Quote: Originally posted by arkoma  
fractional distillation of EtOH. notice the SM patch......





I keep noticing the nice periodic table.
View user's profile Visit user's homepage View All Posts By User
arkoma
Forum Redneck
*****




Posts: 1525
Registered: 3-2-2014
Location: Lago de Chapala, el lado norte
Member Is Offline

Mood: Nahua

[*] posted on 4-2-2021 at 15:08


Success!!! CaO. Roasted pickling lime at a red heat for an hour. Put a couple grams in a piece of foil and dripped water on it, and it proceeded to get HOT and sizzle. YAY. 99% EtOH here I come!!!



Quote:
Travel is fatal to prejudice, bigotry, and narrow-mindedness, and many of our people need it sorely on these accounts.

Mark Twain


Smash. All. Icons
View user's profile View All Posts By User
arkoma
Forum Redneck
*****




Posts: 1525
Registered: 3-2-2014
Location: Lago de Chapala, el lado norte
Member Is Offline

Mood: Nahua

[*] posted on 5-2-2021 at 20:26
Broke the EtOH and H2O Azeoterope, yippee!!


Had a terrible recovery, but don't care, I broke the ^&^%&*$ azeotrope!!!
Been an obsession.....

50 gms CaO and 250ml of 95% EtOH were refluxed for five hours, then allowed to sit for 8. I kept my moisture discipline up (drying tubes, quick stoppering, oven dried glass), and when I distilled the mixture I got 70mls that read about 98-99 on my hydrometer (my house just happened to be 20C inside, no temperature corrections necessary).

Procedure from Vogel's Third.




Quote:
Travel is fatal to prejudice, bigotry, and narrow-mindedness, and many of our people need it sorely on these accounts.

Mark Twain


Smash. All. Icons
View user's profile View All Posts By User
Sulaiman
International Hazard
*****




Posts: 3141
Registered: 8-2-2015
Location: UK ... on extended Holiday in Malaysia
Member Is Offline


[*] posted on 11-2-2021 at 17:48
What happened to my potassium permanganate ?


Some re-crystallised potassium permanganate

kmno4 start.jpg - 833kB

I left the KMnO4 crystals exposed to air for a couple of weeks,
in the cupboard where I keep glassware and solid chemicals in 'sealed' containers - no liquids,
and found this

kmno4 after.jpg - 1.1MB

what happened ? what are the white crystals ?

(the most volatile substances in the cupboard are;
ammonium bicarbonate, TCCA, sodium metabisulphite
... all kept in glass bottles)




CAUTION : Hobby Chemist, not Professional or even Amateur
View user's profile View All Posts By User
arkoma
Forum Redneck
*****




Posts: 1525
Registered: 3-2-2014
Location: Lago de Chapala, el lado norte
Member Is Offline

Mood: Nahua

[*] posted on 13-2-2021 at 09:59
Unknown metal oxide


Wasn't my intent, but when melting some white metal the other night I inadvertently got some (X)O. Opened the front of my furnace and there was what looked like and actual flame coming off the crucible content.


20210213_123606.jpg - 2.9MB




Quote:
Travel is fatal to prejudice, bigotry, and narrow-mindedness, and many of our people need it sorely on these accounts.

Mark Twain


Smash. All. Icons
View user's profile View All Posts By User
Texium
Administrator
********




Posts: 3611
Registered: 11-1-2014
Location: Salt Lake City
Member Is Online

Mood: Triturated

[*] posted on 23-2-2021 at 19:47


Testing to see if posting to this thread works...



Come check out the Official Sciencemadness Wiki
They're not really active right now, but here's my YouTube channel and my blog.
View user's profile Visit user's homepage View All Posts By User
Piroz
Harmless
*




Posts: 19
Registered: 15-12-2020
Location: Poland
Member Is Offline


[*] posted on 24-2-2021 at 12:50


I used my furnance to preparation calcium oxide from old, carbonated slaked lime. I need CaO for preaparation both ammonia and calcium nitrate.

https://youtu.be/d6vDtND4HSU
View user's profile View All Posts By User
Bedlasky
International Hazard
*****




Posts: 895
Registered: 15-4-2019
Location: Beleriand
Member Is Offline


[*] posted on 26-2-2021 at 15:11


Currently waiting for crystals of copper(II) tris complexes - specifically [Cu(H-1tris)2(H2O)] and [Cu(tris)4](ClO4)2. The latter one should be energetic.



If you are interested in aqueous inorganic chemistry look at https://colourchem.wordpress.com/main-page/

I can offer GC analysis of samples. Just U2U to me for more info.

"An old friend once told me something that gave me great comfort. Something he had read. He said that Mozart, Beethoven and Chopin never died. They simply became music." Dr. Robert Ford, Westworld
View user's profile Visit user's homepage View All Posts By User
j_sum1
Administrator
********




Posts: 5573
Registered: 4-10-2014
Location: Oz
Member Is Online

Mood: Taking opportunities to breathe.

[*] posted on 5-3-2021 at 21:21


Did some titration with my son. Just for the fun of it.
Tried out a few different indicators. And he got to play with some precise measuring equipment.

IMG20210306150758.jpg - 2.8MB
View user's profile View All Posts By User
ChemTalk
Hazard to Self
**




Posts: 64
Registered: 13-12-2018
Location: United States
Member Is Offline

Mood: colloidal

[*] posted on 6-3-2021 at 08:24


Quote: Originally posted by j_sum1  
Did some titration with my son. Just for the fun of it.
Tried out a few different indicators. And he got to play with some precise measuring equipment.



Oh, that's awesome, sounds like fun. My son might do some chemistry this weekend also.
View user's profile Visit user's homepage View All Posts By User
njl
International Hazard
*****




Posts: 585
Registered: 26-11-2019
Location: under the sycamore tree
Member Is Offline

Mood: ambivalent

[*] posted on 6-3-2021 at 09:24


What the heck is the difference between diazomethane and methane diazonium salt? Other than the obvious structural difference. How do their reactivities compare? One review says they're completely different and yet another implies they are interchangeable. Can diazonium compounds eliminate H+ to form a diazo compound?



Reflux condenser?? I barely know her!
View user's profile View All Posts By User
Texium
Administrator
********




Posts: 3611
Registered: 11-1-2014
Location: Salt Lake City
Member Is Online

Mood: Triturated

[*] posted on 6-3-2021 at 15:12


Diazomethane is a highly unstable and reactive gas, but it is still isolable and finds a lot of use in synthesis. The methyldiazonium ion makes it looks tame by comparison. It is so unstable that it is only observed transiently. Aliphatic diazonium salts are generally far too reactive to be synthetically useful or safe, while aryl diazonium salts are significantly more stable. In the future, please cite these “reviews” that you speak of. I don’t know why anyone would say that the two species are equivalent. Perhaps they exist in equilibrium, under certain conditions, but they are not the same thing.



Come check out the Official Sciencemadness Wiki
They're not really active right now, but here's my YouTube channel and my blog.
View user's profile Visit user's homepage View All Posts By User
Piroz
Harmless
*




Posts: 19
Registered: 15-12-2020
Location: Poland
Member Is Offline


[*] posted on 8-3-2021 at 15:20


Finally I got potassium chloride from wood ashes practically free from sodium compounds. I used crystallisation from saturated hot solution in plastic bottle (>50 deg. C), sodium was removed in crystalline mass, leaved potassium chloride in the solution. However crystallisation from cold solution (several times) wasn't enough to remove some sodium.
Flame analysis suprised me, potassium chloride from chem store reffered as 99% purity have more sodium than my potassium chloride from wood ashes.

Flame_colour1.jpg - 60kB Flame_colour2.jpg - 50kB Flame_colour3.jpg - 53kB Flame_colour4.jpg - 42kB

[Edited on 8-3-2021 by Piroz]
View user's profile View All Posts By User
j_sum1
Administrator
********




Posts: 5573
Registered: 4-10-2014
Location: Oz
Member Is Online

Mood: Taking opportunities to breathe.

[*] posted on 8-3-2021 at 15:27


Nice work, Piroz.
View user's profile View All Posts By User
njl
International Hazard
*****




Posts: 585
Registered: 26-11-2019
Location: under the sycamore tree
Member Is Offline

Mood: ambivalent

[*] posted on 8-3-2021 at 16:05


Is there a conclusion one can draw from that?



Reflux condenser?? I barely know her!
View user's profile View All Posts By User
arkoma
Forum Redneck
*****




Posts: 1525
Registered: 3-2-2014
Location: Lago de Chapala, el lado norte
Member Is Offline

Mood: Nahua

[*] posted on 8-3-2021 at 21:41


Yes, from the flame colors. Takes barely any Na ions to color a flame yellow. The hot xtallized KCl is a lovely violet.

*edit* Conclusion being that his own work-up had a much better flame color. obviously violet, unlike the commercial. Hence his contained less Na ion.

[Edited on 3-9-2021 by arkoma]




Quote:
Travel is fatal to prejudice, bigotry, and narrow-mindedness, and many of our people need it sorely on these accounts.

Mark Twain


Smash. All. Icons
View user's profile View All Posts By User
Bezaleel
National Hazard
****




Posts: 420
Registered: 28-2-2009
Member Is Offline

Mood: transitional

[*] posted on 11-3-2021 at 15:05


Good job, Piroz!
View user's profile View All Posts By User
Elemental Phosphorus
Hazard to Others
***




Posts: 166
Registered: 11-11-2016
Location: Is everything
Member Is Offline

Mood: No Mood

[*] posted on 14-3-2021 at 20:04


I just did a little extraction of capsaicin from dried habaneros, hope to do it on a larger scale this week, but it was just a small scale run.

Wish I had a soxhlet extractor to use, but I just used boiling acetone in a flask and then poured it off and evaporated. Final product was a little bit of orange oil, and of course I had to taste a tiny bit, so I just put a knife tip in it and tasted it and it was definitely spicy (I know it’s not best practice, but I had to try).

Also did woelen’s demonstration with the oxidation states of vanadium, since I had some V2O5 laying around.

8B5DF1F0-F235-425C-A2B7-CB597B3BCA29.jpeg - 713kB68900EA0-FEE9-4F00-83DE-695370B208A2.jpeg - 736kB66BD8688-CEEE-44FD-B8FB-E08E75AEBE5E.jpeg - 644kB
View user's profile View All Posts By User
arkoma
Forum Redneck
*****




Posts: 1525
Registered: 3-2-2014
Location: Lago de Chapala, el lado norte
Member Is Offline

Mood: Nahua

[*] posted on 15-3-2021 at 18:42


i've only used my soxhlet a few times, but it is dang sure a cool piece of gear. seems like it was <$30US from nanshinglass



Quote:
Travel is fatal to prejudice, bigotry, and narrow-mindedness, and many of our people need it sorely on these accounts.

Mark Twain


Smash. All. Icons
View user's profile View All Posts By User
Bezaleel
National Hazard
****




Posts: 420
Registered: 28-2-2009
Member Is Offline

Mood: transitional

[*] posted on 16-3-2021 at 12:42


Vacuum setup repairs
The rotary vane pump I use is not really suited for pumping on liquids which give off corrosive fumes. Obviously, if you ignore that, then your setup will degrade over time. I took apart several joints of the type shown in the picture.
IMG_3654.JPG - 416kB
On the majority of the flanges, there was corrosion, revealing itself as white powdery crusts. Typically, the components shown are made of aluminium, which is a really bad choice for components used in a corrosive environment. (But who would dare to complain when you receive all of this for free?)

Anyway, there are two points of interest:
* For one joint I did not have a spacer when I received the vacuum components, and I made one from PTFE on a lathe (shown in the photo). The connection which had this spacer was much less corroded than the joints which have aluminium spacers.
* I polished the flanges with a household grinding pad and some household grinding/polishing powder, washed it and let everything dry over night. I re-assembled it the other day using a very small amount of silicone vacuum grease on the flanges and the O-rings.

When I pulled a vacuum I was disappointed to stay at 10 mBar of pressure, but after the system had dried for another day, it rapidly went down to the limit of my pressure gauge. So apparently, it was due to droplets of water which were evaporating that the pressure initially stayed at 10mBar.
View user's profile View All Posts By User
njl
International Hazard
*****




Posts: 585
Registered: 26-11-2019
Location: under the sycamore tree
Member Is Offline

Mood: ambivalent

[*] posted on 18-3-2021 at 06:55


How will the basicity of sodium isopropoxide compare to that of sodium methoxide in the claisen condensation, and how might that effect the reaction outcome? I can't find anything detailing NaOiPr properties.



Reflux condenser?? I barely know her!
View user's profile View All Posts By User
DraconicAcid
International Hazard
*****




Posts: 3832
Registered: 1-2-2013
Location: The tiniest college campus ever....
Member Is Offline

Mood: Semi-victorious.

[*] posted on 18-3-2021 at 09:02


Quote: Originally posted by njl  
How will the basicity of sodium isopropoxide compare to that of sodium methoxide in the claisen condensation, and how might that effect the reaction outcome? I can't find anything detailing NaOiPr properties.


I would expect it to be slightly more basic, but suitable.

PS- anyone know if magnesium alkoxides would work in that reaction? I've got far more magnesium than sodium.....

[Edited on 18-3-2021 by DraconicAcid]




Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
View user's profile View All Posts By User
njl
International Hazard
*****




Posts: 585
Registered: 26-11-2019
Location: under the sycamore tree
Member Is Offline

Mood: ambivalent

[*] posted on 18-3-2021 at 09:35


Yes, I believe even MgO can be used to form the basic species.



Reflux condenser?? I barely know her!
View user's profile View All Posts By User
 Pages:  1  ..  8    10  

  Go To Top