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

Printable Version  
 Pages:  1  ..  49    51    53  ..  98
Author: Subject: The Short Questions Thread (4)
Texium
Administrator
********




Posts: 3881
Registered: 11-1-2014
Location: Salt Lake City
Member Is Offline

Mood: Triturated

[*] posted on 31-1-2016 at 11:02


Quote: Originally posted by lysander  
Quote: Originally posted by zts16  
Not a very good deal, but this is the first thing that came up on Google shopping: http://www.rakuten.com/prod/sodium-ferrocyanide-laboratory-c...

Oh wait, is this a regulated chemical in the U.S.? I've gotten so used to easy access to K-ferrocyanide I didn't consider there might be a difference with the Na salt.
Nope, not regulated at all. It's just that the potassium salt is used more often for some reason. I'm not sure why, being as usually sodium salts are less expensive, the two are made by the same process, and can be used interchangeably most of the time. It's also not one of those situations where the sodium salt is hygroscopic, which seems to be one of the main reasons why potassium salts are preferred in some cases, such as with bisulfate.



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
lysander
Hazard to Self
**




Posts: 69
Registered: 12-7-2015
Member Is Offline

Mood: No Mood

[*] posted on 31-1-2016 at 12:52
Sodium ferrocyanide


Quote: Originally posted by zts16  
Nope, not regulated at all. It's just that the potassium salt is used more often for some reason. I'm not sure why, being as usually sodium salts are less expensive, the two are made by the same process, and can be used interchangeably most of the time. It's also not one of those situations where the sodium salt is hygroscopic, which seems to be one of the main reasons why potassium salts are preferred in some cases, such as with bisulfate.


Well both ferrocyanides are hygroscopic -- the K-salt forms a trihydrate and the Na-salt forms a decahydrate. But while I can find plenty of suppliers of bulk K-ferrocyanide the only bulk Na-ferrocyanide I have found so far is from a U.S. supplier in OK on ebay claiming a bizarre set of "hazardous chemical" regulations apply to this common anti-caking agent!
View user's profile View All Posts By User
Texium
Administrator
********




Posts: 3881
Registered: 11-1-2014
Location: Salt Lake City
Member Is Offline

Mood: Triturated

[*] posted on 31-1-2016 at 12:53


Sorry, I meant to say deliquescent.



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
JJay
International Hazard
*****




Posts: 3440
Registered: 15-10-2015
Member Is Offline


[*] posted on 31-1-2016 at 13:01


Quote: Originally posted by Velzee  
Okay, I went out searching for any radioactive rock specimens near my home( I found one), and I found this other guy here(who seems not to be radioactive):



So I want to know if this is coal(specifically anthracite coal), any guesses?
It's light, has a metallic luster with a few brownish spots here and there. I actually find quite a bit of this stuff scattered around my neighborhood. All on the surface/stick out to the surface.

EDIT: With some effort, it even writes like a very fine, very light pencil.

[Edited on 1/29/2016 by Velzee]

[Edited on 1/29/2016 by Velzee]


That looks like shale, but it's hard to be really sure from the image.
View user's profile View All Posts By User
Deathunter88
National Hazard
****




Posts: 483
Registered: 20-2-2015
Location: Beijing, China
Member Is Offline

Mood: No Mood

[*] posted on 2-2-2016 at 23:23
Solvent substitution


Are there any good alternative solvents for acetone (regulated drug precursor)? I want something similar to acetone that I can use to rinse glassware after washing and something that is good at removing glue. The usual substitutes such as MEK, ether, and chloroform are out since they are drug precursors too. I'm thinking ethanol for rinsing glassware but I am not sure. While on this topic, is xylene a good substitute for toluene(also drug precursor) in regards to it's solvent properties, such as for recrystallizing things? If not are there good substitutes for toluene?
View user's profile View All Posts By User
greenlight
International Hazard
*****




Posts: 689
Registered: 3-11-2014
Member Is Offline

Mood: Energetic

[*] posted on 3-2-2016 at 01:57


I have used 99% Ethanol for washing glassware before and it does a good job, I usually use acetone though and find it the best for regular cleaning. Sucks you can't purchase it in your country. I don't really see how it is an actual precursor for illicit drugs, maybe to clean and crystallize the final product but not for the actual synthesis.

I am sure that you can use xylene as a substitute for toluene for general solvent properties like you state.




The only use for an atomic bomb is to keep somebody else from using one.
George Wald
View user's profile View All Posts By User
confused
Hazard to Others
***




Posts: 244
Registered: 17-3-2013
Location: Singapore
Member Is Offline

Mood: tired

[*] posted on 3-2-2016 at 03:45
Question about ball mill


I'm trying to make a ball mill to increase the surface area of various metals and chemicals (stuff always clumps :( )
I'm trying to use glass marbles as grinding media, is there anything i should take note of, If i'm not grinding any energetic materials
View user's profile View All Posts By User
Deathunter88
National Hazard
****




Posts: 483
Registered: 20-2-2015
Location: Beijing, China
Member Is Offline

Mood: No Mood

[*] posted on 3-2-2016 at 04:46


Quote: Originally posted by greenlight  
I have used 99% Ethanol for washing glassware before and it does a good job, I usually use acetone though and find it the best for regular cleaning. Sucks you can't purchase it in your country. I don't really see how it is an actual precursor for illicit drugs, maybe to clean and crystallize the final product but not for the actual synthesis.

I am sure that you can use xylene as a substitute for toluene for general solvent properties like you state.


Thanks for your answer. I'll use ethanol from now on to wash glassware.
View user's profile View All Posts By User
Deathunter88
National Hazard
****




Posts: 483
Registered: 20-2-2015
Location: Beijing, China
Member Is Offline

Mood: No Mood

[*] posted on 3-2-2016 at 04:48


Quote: Originally posted by confused  
I'm trying to make a ball mill to increase the surface area of various metals and chemicals (stuff always clumps :( )
I'm trying to use glass marbles as grinding media, is there anything i should take note of, If i'm not grinding any energetic materials


Using glass as grinding media can have the issue of getting glass chips mixed with your chemicals. I wouldn't grind the chemicals as I think it will only make the clumping worse. Also, finer chemicals also means more dust which can be annoying.
View user's profile View All Posts By User
The Volatile Chemist
International Hazard
*****




Posts: 1973
Registered: 22-3-2014
Location: 'Stil' in the lab...
Member Is Offline

Mood: Copious

[*] posted on 3-2-2016 at 16:02


Indeed, dust is annoying. In regards to finding Potassium Ferrocyanide, you'd be best buying it. Since the sodium salt is about 1/3 as soluble as the potassium one, I'd try crystallizing the sodium salt from the potassium one and sufficient table salt.

[Edited on 2-4-2016 by The Volatile Chemist]




View user's profile Visit user's homepage View All Posts By User
bluamine
Hazard to Others
***




Posts: 177
Registered: 17-8-2015
Member Is Offline

Mood: No Mood

biggrin.gif posted on 4-2-2016 at 09:05
what are the most easily available nickel compounds & their uses


Hi everyone!!!
I want to use nickel as a catalyst for several reactions, & I hope I will find someone who can help me. I would like to know easily home-available chemicals containing it.
View user's profile View All Posts By User
UC235
International Hazard
*****




Posts: 550
Registered: 28-12-2014
Member Is Offline

Mood: No Mood

[*] posted on 4-2-2016 at 09:18


Nickel salts are carcinogenic and allergenic in a large portion of the population, so they are found in no consumer products. You might be able to buy oxide or carbonate as an additive for pottery glazes, but that's all. Buy nickel metal and make your own starting from nickel nitrate.

[Edited on 4-2-2016 by UC235]
View user's profile View All Posts By User
Texium
Administrator
Threads Merged
4-2-2016 at 09:26
PHILOU Zrealone
International Hazard
*****




Posts: 2880
Registered: 20-5-2002
Location: Brussel
Member Is Offline

Mood: Bis-diazo-dinitro-hydroquinonic

[*] posted on 4-2-2016 at 15:26


Quote: Originally posted by bluamine  
Hi everyone!!!
I want to use nickel as a catalyst for several reactions, & I hope I will find someone who can help me. I would like to know easily home-available chemicals containing it.

Hint coins and metalic money often contain such an element.
Even if its use is reduced you may stil find nickel to some extend into 1€ and 2€ coins...aside with copper and other metals.

1 Euro coins: 7,50g
-Bronze External ring contains nickel brass (maillechort)
75% Cu, 20% Zn and 5% Ni (75 Cu/20 Zn/5 Ni)
-Silver Internal ring contains layers of copper-nickel alloy (75% Cu and 25% Ni - 75 Cu/25 Ni + traces of Mn) and nickel


2 Euro coins: 8,50g
-Silver External ring contains copper-nickel alloy (75% Cu and 25% Ni - 75 Cu/25 Ni + traces of Mn).
-Bronze Internal ring contains layers of nickel brass (maillechort)
75% Cu, 20% Zn and 5% Ni (75 Cu/20 Zn/5 Ni) and nickel

Of course dissolving 1€ and 2€ coins in sulfuric or nitric acid is against the laws because you destroy money. ;)
So don't tell anyone where your Ni comes from ;););)

[Edited on 5-2-2016 by PHILOU Zrealone]




PH Z (PHILOU Zrealone)

"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
View user's profile View All Posts By User
DraconicAcid
International Hazard
*****




Posts: 3964
Registered: 1-2-2013
Location: The tiniest college campus ever....
Member Is Offline

Mood: Semi-victorious.

[*] posted on 5-2-2016 at 20:47


Quote: Originally posted by UC235  
Quote: Originally posted by learningChem  
Is it possible to reduce 3 nitrobenzoic acid to 3 aminobenzoic acid using the Fe/HCl method?


Yes. Tin and HCl would also work. However, I would recommend using a reducing agent in basic media instead. Having soluble 3-nitrobenzoate will improve reaction speed.

Options are sodium dithionite/hydrosulfite, thiourea dioxide in NaOH or NH3 solution or Na2S (which reeks and poses a hazard on neutralization).


Would aluminum in sodium hydroxide work?




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
UC235
International Hazard
*****




Posts: 550
Registered: 28-12-2014
Member Is Offline

Mood: No Mood

[*] posted on 5-2-2016 at 20:52


Quote: Originally posted by DraconicAcid  
Quote: Originally posted by UC235  
Quote: Originally posted by learningChem  
Is it possible to reduce 3 nitrobenzoic acid to 3 aminobenzoic acid using the Fe/HCl method?


Yes. Tin and HCl would also work. However, I would recommend using a reducing agent in basic media instead. Having soluble 3-nitrobenzoate will improve reaction speed.

Options are sodium dithionite/hydrosulfite, thiourea dioxide in NaOH or NH3 solution or Na2S (which reeks and poses a hazard on neutralization).


Would aluminum in sodium hydroxide work?


I would guess rather poorly, but maybe. Workup would probably be terrible from gelatinous aluminum hydroxide. Avoiding reduction to nitrosobenzene, azobenzene, phenylhydroxylamine and hydrazobenzenes is important. As far as I know, zinc in NaOH typically produces hydrazobenzene which is then acidified for the benzidine rearrangement. Aluminum may be similar.

Hydrosulfite is the classical last step for luminol production to reduce an aromatic nitro group in basic conditions. I have successfully used thiourea dioxide in its place based on a paper that reduces a wide range of aromatic nitro compounds to anilines using it.

Na2S is a classic, albeit smelly approach to anilines.

You caught me before I deleted the comment. I accidentally replied to something from page 26. :D

[Edited on 6-2-2016 by UC235]
View user's profile View All Posts By User
Romix
National Hazard
****




Posts: 277
Registered: 19-6-2015
Member Is Offline

Mood: No Mood

[*] posted on 8-2-2016 at 02:40
Boiling point.


Why alcohols have lower boiling point then water.

They all have heavier molecular mass then H2O, but boils at lower temp.
Maybe because of attractions between molecules, and water needs more energy to brake these? Or no?

[Edited on 8-2-2016 by Romix]
View user's profile View All Posts By User
hissingnoise
International Hazard
*****




Posts: 3940
Registered: 26-12-2002
Member Is Offline

Mood: Pulverulescent!

[*] posted on 8-2-2016 at 03:18


Quote:
Maybe because of attractions between molecules, and water needs more energy to brake these?

Essentially yes! Ethanol is less polar than water . . .

Solvent relative polarities.

View user's profile View All Posts By User
Fulmen
International Hazard
*****




Posts: 1611
Registered: 24-9-2005
Member Is Offline

Mood: Bored

[*] posted on 8-2-2016 at 03:51


Good question and you're absolutely right about the cause:
http://chemistry.elmhurst.edu/vchembook/163boilingpt.html




We're not banging rocks together here. We know how to put a man back together.
View user's profile View All Posts By User
Magpie
lab constructor
*****




Posts: 5939
Registered: 1-11-2003
Location: USA
Member Is Offline

Mood: Chemistry: the subtle science.

[*] posted on 8-2-2016 at 09:04


"hydrogen bonding" for the water.



The single most important condition for a successful synthesis is good mixing - Nicodem
View user's profile View All Posts By User
Texium
Administrator
Threads Merged
8-2-2016 at 09:09
symboom
International Hazard
*****




Posts: 1133
Registered: 11-11-2010
Location: Wrongplanet
Member Is Offline

Mood: Doing science while it is still legal since 2010

[*] posted on 13-2-2016 at 01:26
reaction of red phosphorus and ammonium hydroxide


ive mixed the two in a process to extract potassium chlorate from matches and part of it is to add ammonium hydroxide to the mix. Not sure if it is a reaction or so it seems is it reacting if so what is formed or

[Edited on 13-2-2016 by symboom]
View user's profile View All Posts By User
j_sum1
Administrator
********




Posts: 5753
Registered: 4-10-2014
Location: Unmoved
Member Is Offline

Mood: Possessor of a tidy and organised lab. Now to mess it up again.

[*] posted on 14-2-2016 at 02:19


I have decided that I will prepare a silver mirror and a copper mirror (using hydrazine) on the inside of some ampoules for my element collection.
Is a gold mirror also possible? I have tried searching for "gold mirror" but can't get past all the junk. (Need to improve my googe-fu.) I assume that it is possible but have not found a procedure.




View user's profile View All Posts By User
j_sum1
Administrator
********




Posts: 5753
Registered: 4-10-2014
Location: Unmoved
Member Is Offline

Mood: Possessor of a tidy and organised lab. Now to mess it up again.

[*] posted on 14-2-2016 at 03:00
Faulty pH meter


I have a pH meter similar to the one shown.
meStez9KXzwEPE4kUEZIVjg.jpg - 14kB
I went to use it today and found it reading abnormally high -- 9.5 for something that should be neutral or close to it. (Swimming pool.)
I keep it in a screw-top jar in a buffer solution at 6.86.

What may have happened to it? Is there anything that can be done to restore it? Or do i just need to replace it?




View user's profile View All Posts By User
Kagutsuchi
Hazard to Self
**




Posts: 51
Registered: 21-6-2015
Location: Hungary
Member Is Offline

Mood: Happy

[*] posted on 19-2-2016 at 13:33
What can I do with tin?


I recently found out that I have about 10 kg of very fine tin powder. Any ideas what could I do with it?
View user's profile View All Posts By User
Texium
Administrator
Threads Merged
19-2-2016 at 13:49
Metacelsus
International Hazard
*****




Posts: 2505
Registered: 26-12-2012
Location: Boston, MA
Member Is Offline

Mood: Double, double, toil and trouble

[*] posted on 19-2-2016 at 15:22


You could use it with HCl for reductions (for example, nitrotoluene to toluidine).



As below, so above.
View user's profile View All Posts By User
CharlieA
International Hazard
*****




Posts: 620
Registered: 11-8-2015
Location: Missouri, USA
Member Is Offline

Mood: No Mood

[*] posted on 19-2-2016 at 19:03


Quote: Originally posted by j_sum1  
I have a pH meter similar to the one shown.

I went to use it today and found it reading abnormally high -- 9.5 for something that should be neutral or close to it. (Swimming pool.)
I keep it in a screw-top jar in a buffer solution at 6.86.

What may have happened to it? Is there anything that can be done to restore it? Or do i just need to replace it?


I have a similar meter and just rechecked the calibration after the probe had been dry for a couple of months. After hydrating in D. H2O for 15', I than checked two buffers and both were right on...but forget the hundredths reading. Certainly the accuracy to 0.1 pH unit is satisfactory.

Do you have an independent measurement of the pH of your pool water? Even test papers like pHydrion paper or litmus paper (you need to check with both red and blue papers) could give you some idea. Is the pool chlorinated now?
View user's profile View All Posts By User
 Pages:  1  ..  49    51    53  ..  98

  Go To Top