| Pages:
1
..
12
13
14
15
16
..
103 |
Zyklon-A
International Hazard
Posts: 1547
Registered: 26-11-2013
Member Is Offline
Mood: Fluorine radical
|
|
It's not hard to make one.http://chem.wisc.edu/deptfiles/genchem/lab/labdocs/modules/e....
Metal will not work.
I don't know what you are trying to make, but I made this and it will likely work for whatever you are trying to make.
[Edited on 11-2-2014 by Zyklonb]
|
|
|
Boron Trioxide
Harmless
Posts: 42
Registered: 18-6-2012
Member Is Offline
Mood: No Mood
|
|
Sodium hydroxide was one thing I was looking at making, but the main problem was with using soaked paper or similar device is that such a device only
allows a small amount of current, but I will give the agar a try if I can find some.
Though won't the metal allow current just like the salt bridge, I know for sodium hydroxide you couldn't use aluminium but couldn't iron or zinc work?
But thanks for your links and help
|
|
|
Zyklon-A
International Hazard
Posts: 1547
Registered: 26-11-2013
Member Is Offline
Mood: Fluorine radical
|
|
Yes I ran into that exact problem, soaked paper only allows a small amount of current. It did work, but at about 3 amps it took about 2 days of
constant running just to get to 14 Ph, almost nothing. I eventually gave up and just bought my NaOH.
I don't know why metal wont work, but I know it wont.
|
|
|
elementcollector1
International Hazard
Posts: 2684
Registered: 28-12-2011
Location: The Known Universe
Member Is Offline
Mood: Molten
|
|
I experimented with alternative salt bridges such as gelatin and other such, to no effect. My advice would be to take a length of rubber tubing, and
fill it with concentrated salt solution before stuffing it at both ends with cotton. This *might* allow for more current...
Elements Collected:52/87
Latest Acquired: Cl
Next in Line: Nd
|
|
|
Oscilllator
National Hazard
Posts: 659
Registered: 8-10-2012
Location: The aqueous layer
Member Is Offline
Mood: No Mood
|
|
When sodium thiosulfate reduces potassium permanganate in a basic solution, a green colour even stronger than the permanganate forms. Why is this?
I couldn't find any info on this online.
|
|
|
HeYBrO
Hazard to Others
Posts: 289
Registered: 6-12-2013
Location: 'straya
Member Is Offline
Mood: 
|
|
Quote: Originally posted by Oscilllator  | When sodium thiosulfate reduces potassium permanganate in a basic solution, a green colour even stronger than the permanganate forms. Why is this?
|
I would say it is because of the reduction to manganate, the same can be seen in the famous chemical chameleon reaction. equation for reduction
:MnO4- + e- → MnO4-2
Other members can fill in any gaps as I'm not sure other wise for this one.
|
|
|
TheChemiKid
Hazard to Others
Posts: 493
Registered: 5-8-2013
Location: ̿̿ ̿̿ ̿'̿'̵͇̿̿з=༼ ▀̿̿Ĺ̯̿̿▀̿ ̿ ༽
Member Is Offline
Mood: No Mood
|
|
What is the easiest way to separate Ethylbenzene and Xylene?
I have hardware store "Xylene" which contains 70-90% mixed Xylenes and 10-30% Ethylbenzene.
When the police come
\( * O * )/ ̿̿ ̿̿ ̿'̿'̵͇̿̿з=༼ ▀̿̿Ĺ̯̿̿▀̿ ̿ ༽
|
|
|
testimento
Hazard to Others
Posts: 351
Registered: 10-6-2013
Member Is Offline
Mood: No Mood
|
|
Just a theory, but ethylbenzene melts at -95C where p-Xylene melts at 13C, so could it be crystallized out of the ethylbenzene?
Is this reaction real and balanced:
1 Ca(OH)2 + 1 CO(NH2)2 = 1 CaCO3 + 2 NH3
Theory: the calcium hydroxide should donate two hydrogens for ammonia and obtain the carbon monoxide and two oxygens to make calcium carbonate.
If not, are there any decent ways to make ammonia from urea except pyrolysis?
[Edited on 11-2-2014 by testimento]
|
|
|
TheChemiKid
Hazard to Others
Posts: 493
Registered: 5-8-2013
Location: ̿̿ ̿̿ ̿'̿'̵͇̿̿з=༼ ▀̿̿Ĺ̯̿̿▀̿ ̿ ༽
Member Is Offline
Mood: No Mood
|
|
A mix of xylenes melts at -47.4°C, though.
When the police come
\( * O * )/ ̿̿ ̿̿ ̿'̿'̵͇̿̿з=༼ ▀̿̿Ĺ̯̿̿▀̿ ̿ ༽
|
|
|
DraconicAcid
International Hazard
Posts: 4278
Registered: 1-2-2013
Location: The tiniest college campus ever....
Member Is Offline
Mood: Semi-victorious.
|
|
| Quote: Originally posted by testimento | | Just a theory, but ethylbenzene melts at -95C where p-Xylene melts at 13C, so could it be crystallized out of the ethylbenzene?
|
I really doubt it. You've got a four-component system there- ethylbenzene, o-xylene, m-xylene, and p-xylene. They are sufficiently similar that I'd
use any two of them as a textbook example of an ideal solution. Even at temperatures well below 13 oC, p-xylene would be very soluble in
ethylbenzene. If you cool it in dry ice, you may see some xylenes crystallizing out, and the ethylbenzene would stay in the liquid phase. It doesn't
seem like a great separation method, though.
Why do you want to separate them?
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.
|
|
|
testimento
Hazard to Others
Posts: 351
Registered: 10-6-2013
Member Is Offline
Mood: No Mood
|
|
vanillin
Could vanillin be synthetized how reasonably?
|
|
|
bfesser
Resident Wikipedian
Posts: 2114
Registered: 29-1-2008
Member Is Offline
Mood: No Mood
|
|
Yes. Try Google. This [was] off-topic. Please don't ask for spoon-feeding.
[Edited on 11.2.14 by bfesser]
|
|
|
bfesser
|
Threads Merged
11-2-2014 at 14:41 |
TheChemiKid
Hazard to Others
Posts: 493
Registered: 5-8-2013
Location: ̿̿ ̿̿ ̿'̿'̵͇̿̿з=༼ ▀̿̿Ĺ̯̿̿▀̿ ̿ ༽
Member Is Offline
Mood: No Mood
|
|
Can Phenylacetic Acid be synthesized using the same method as Benzoic Acid from Toluene or Phthalic Acid from o-Xylene (KMnO4 and reflux).
I expect it can, but I want to be sure before using my Ethylbenzene.
When the police come
\( * O * )/ ̿̿ ̿̿ ̿'̿'̵͇̿̿з=༼ ▀̿̿Ĺ̯̿̿▀̿ ̿ ༽
|
|
|
bfesser
Resident Wikipedian
Posts: 2114
Registered: 29-1-2008
Member Is Offline
Mood: No Mood
|
|
No, KMnO<sub>4</sub> & reflux yields benzoic acid.
Attachment: Chem263_Oct12_notes_2010.pdf (475kB)
This file has been downloaded 1332 times
|
|
|
Crowfjord
Hazard to Others
Posts: 390
Registered: 20-1-2013
Location: Pacific Northwest
Member Is Offline
Mood: Ever so slowly crystallizing...
|
|
Nope. The benzylic carbon would be oxidized, as it is much more reactive than the terminal methyl. Depending on how much oxidant is used (or how
strong it is), one would expect to get phenylmethylcarbinol, acetophenone, or benzoic acid.
[Edit] Aw, darn it bfesser, you beat me to it! ;P
[Edited on 11-2-2014 by Crowfjord]
|
|
|
Zyklon-A
International Hazard
Posts: 1547
Registered: 26-11-2013
Member Is Offline
Mood: Fluorine radical
|
|
I search but couldn't find the solubility of cadmium sulfate in sulfuric acid. I plan on purifying some cadmium (from Ni-Cd batteries), by dissolving
in H2SO4.
Does anyone know anything about it?
I plan on using an excess of sulfuric acid because it is contaminated with Cd(OH)2, but I don't know what the proportions are.
Cd + H2SO4 → CdSO4 + H2.
Cd(OH)2+ H2SO4→2H2O+ CdSO4.
[Edited on 13-2-2014 by Zyklonb]
[Edited on 13-2-2014 by Zyklonb]
|
|
|
DraconicAcid
International Hazard
Posts: 4278
Registered: 1-2-2013
Location: The tiniest college campus ever....
Member Is Offline
Mood: Semi-victorious.
|
|
If you don't use too much of an excess, you only have to worry about its solubility in water.
<!-- bfesser_edit_tag -->[<a href="u2u.php?action=send&username=bfesser">bfesser</a>: removed
broken BBCode quote]
[Edited on 15.2.14 by bfesser]
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.
|
|
|
Zyklon-A
International Hazard
Posts: 1547
Registered: 26-11-2013
Member Is Offline
Mood: Fluorine radical
|
|
I dissolved in slight excess sulfuric acid, soon the reaction got very hot, and turned green. I immediately knew there was nickel(II) sulfate forming
as well. Is there a way to separate the two? Solubility of both sulfates are very close. Single displacement wont work except with cobalt, to
displace nickel. I don't have cobalt.
Any other ways? I'm not trying to encourage spoonfeeding, I just don't know what to do.
[Edited on 13-2-2014 by Zyklonb]
|
|
|
DraconicAcid
International Hazard
Posts: 4278
Registered: 1-2-2013
Location: The tiniest college campus ever....
Member Is Offline
Mood: Semi-victorious.
|
|
| Quote: Originally posted by Zyklonb | I dissolved in slight excess sulfuric acid, soon the reaction got very hot, and turned green. I immediately knew there was nickel(II) sulfate forming
as well. Is there a way to separate the two? Solubility of both sulfates are very close. Single displacement wont work except with cobalt, to
displace nickel. I don't have cobalt.
Any other ways? I'm not trying to encourage spoonfeeding, I just don't know what to do.
[Edited on 13-2-2014 by Zyklonb] |
Cadmium carbonate has a much smaller Ksp than nickel carbonate. Maybe that would 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.
|
|
|
testimento
Hazard to Others
Posts: 351
Registered: 10-6-2013
Member Is Offline
Mood: No Mood
|
|
Does anyone have data what is the electrical conductivity of water with 5-25% NaCl concentration per mm2?
|
|
|
bfesser
Resident Wikipedian
Posts: 2114
Registered: 29-1-2008
Member Is Offline
Mood: No Mood
|
|
testimento (and others), please don't use this thread as a substitute for Google or the CRC Handbook. Also, what the heck do you
mean by "concentration per mm2?"
|
|
|
Brain&Force
Hazard to Lanthanides
Posts: 1302
Registered: 13-11-2013
Location: UW-Madison
Member Is Offline
Mood: Incommensurately modulated
|
|
I think he means conduction per millimeter squared of solution (and that would probably millimeter cubed). Or would it just be millimeters (distance
from one charge to the other)?
At the end of the day, simulating atoms doesn't beat working with the real things...
|
|
|
testimento
Hazard to Others
Posts: 351
Registered: 10-6-2013
Member Is Offline
Mood: No Mood
|
|
I presented it in mm2 because I was thinking of pipe, let's say 100mm2 cross sectional area, where brine would be, and through this should electricity
be conducted. At least the current can be reported mm2 cross sectional area in metals.
And yes, I attempted to search for it for at least half an hour but managed to find no data which I could use as a reference, so I thought to ask.
[Edited on 15-2-2014 by testimento]
|
|
|
bfesser
|
Thread Split
14-2-2014 at 18:10 |
Omnipresent75
Harmless
Posts: 4
Registered: 15-2-2014
Member Is Offline
Mood: No Mood
|
|
I saw a demonstration online, where potassium persulfate was made by following procedure:
45,6 G of ammonium persulpfate dissolved in 100 ml of water
30 G of potassium chloride dissolved in 100 ml of water
Mix the solutions, cool it in fridge, filter crystals out and rinse them with water
Said to yield 54 G K2S2O8, and a leftover solution of Ammonium Chloride.
The said vid on youtube shows said reaction, but .....
So i scoured the WWW for more info on this proces, and found none. Which is why i hope someone here will enlighten me, as i´m out of options.
Is it a Hoax?
Thanks!
|
|
|
papaya
National Hazard
Posts: 615
Registered: 4-4-2013
Member Is Offline
Mood: reactive
|
|
Hello friends, I want to know is there a way to synthesize some Al(NO3)3 starting from Al metal and HNO3 ? I want to have the final salt in as pure
as possible solution(not contaminated with other ions, which will happen if I obtain it by some sort of double decomposition reaction), but as I know
Al doesn't react with nitric acid. Ideas?
|
|
|
| Pages:
1
..
12
13
14
15
16
..
103 |
![[*]](images/xpblue/default_icon.gif){kind=icon}
