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Author: Subject: The Short Questions Thread (4)
MrHomeScientist
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[*] posted on 3-6-2014 at 05:21


Yes, like boiling chips the noodles (like just about anything else) will increase the rate of bubbling by providing lots of nucleation sites. Try the same thing with salt instead of noodles and see if you notice the same effect.
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alexleyenda
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[*] posted on 3-6-2014 at 07:14


Alright, I know I noticed similar effect with other things, but the effect with these noodles is extreme, far stronger than almost anything else, probably because of their huge surface area.
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Pumukli
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[*] posted on 4-6-2014 at 09:19
Suggest an OTC-ish olefine!


Hello All,

Could someone suggest an OTC-ish olefine, which is:
- preferably has the R-CH=CH2 or R-CH=CH-R' structure,
- preferably has its boiling point above 60 Celsius,
- and is not an aromatic one? (I mean one without an aromatic ring.)

By "OTC-ish" I mean: one can get it as an OTC product or can prepare it with a very simple one-step synthesis from an OTC product.

I can think of eugenole and styrene but these are aromatic. Cyclohexene on the other hand is not OTC-ish afaik.

Good brain-storming!

[Edited on 4-6-2014 by Pumukli]
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EdMeese
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[*] posted on 4-6-2014 at 10:13


High-oleic vegetable oil is the first that comes to mind.
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Pumukli
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[*] posted on 4-6-2014 at 11:04


Ah, yeah, unsaturated oils are OTC and boil above 60 C it is sure.

But I'd prefer something more "well-defined", not an oily mixture. And definitely not something poly-olefinic.

But thanks anyway, your suggestion is appropriate for the original (lax) requirements.
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[*] posted on 4-6-2014 at 13:06


Pinene then. Picky picky :-)

Dehydration of menthol should be pretty straighforward.
Maltol isn't "really" aromatic.
If nonconjugated dienes will do you've got a bunch of monoterpenes from flavors: limonene, gerionol, etc.
Allyl hexanoate is pineapple flavor.

Fumaric acid is in some supplement shops, maybe homebrewing.

So, get to it.
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Pumukli
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[*] posted on 6-6-2014 at 07:12


Search is over it seems.
Fumaric acid looks promising.
And is OTC here as well.
And the dehydrated menthol suggestion was also a good one!
Thanks!
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alexleyenda
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[*] posted on 6-6-2014 at 10:09


What would the greenish deposit on copper wire in a chlorate cell (not used as electrode in the liquid, only in the air) be? My guess is copper chloride, am I right?

PS: I know it is not a good idea to put copper in there, I was juste making a small scale test before I get my MMO electrodes for the real thing

[Edited on 6-6-2014 by alexleyenda]
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Zyklon-A
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[*] posted on 6-6-2014 at 13:26


alexleyenda , probably. It will be quite impure, most likely it will be a mixture of copper chloride, copper hydroxide hydrates and lots of other crap.
I once used a copper wire to suspend an MMO anode above the solution. It soon was covered in a green coating as well. Lots of oxygen, minute amounts of chlorine and maybe chlorine oxides are evolved. Also acidified chloride aerosols from bubbling, so it could be many things. The wire soon was so deteriorated, that it just snapped off.
Due to the high amperage I was using, the wire was over 100°C. Hot copper reacts pretty fast with oxygen and chlorine.




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[*] posted on 6-6-2014 at 14:40


Hmmm you are right about the hydroxide, I forgot about that one ! And yeah it did the same thing to me, the wire broke :p That's why I'm testing before I receive my real electrodes !
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[*] posted on 7-6-2014 at 06:45


When an experiment calls for k50 montmorillonite clay, is there anything for which it can be substituted for?
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[*] posted on 7-6-2014 at 06:49


Depends. For one, you didn't quite elaborate on the nature of the "experiment" you speak of. For all we know, this could be something for which kitty litter might suffice.

sparky (~_~)




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[*] posted on 7-6-2014 at 07:37


Thanks, I should have elaborated on that, it's used as a catalyst in the synthesis of 7-hydroxy 4-methylcoumarin as per experiment PG-2 in the following document:

http://www.dst.gov.in/green-chem.pdf
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[*] posted on 8-6-2014 at 06:58


I have an oil burner ignition transformer that puts out 10kv at 23 mA. Is there an easy way to limit that current down to just a few mA? Could a resistor be used to limit the current?



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[*] posted on 8-6-2014 at 08:40


^^yes. Use Ohm's law. Remember that only several milliamps is FATAL if they flow through your heart.



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[*] posted on 8-6-2014 at 14:16


If you use a resistor, you will also drop voltage (the amount depends on your load). Make sure that you use a resistor that can take the power (up to 230 W).

An inductive ballast is also an option. This has the advantage of dissipating less power.




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[*] posted on 10-6-2014 at 12:05


In a chlorate cell, the hydroxide solution you bubbles Cl2 into, does it needs to be replaced from time to time? I guess it does, I just found strange that it was not said in any thread I read about it.

Also, something strange happened in my chlorate cell. It's been running for around 4 hours, I stopped it, but the anode kept bubbling weakly. Any Idea why?

Another also :p I tested the pH of my cell with universal stripes, it did not work, it seemed like it was destroyed by the sample of water. I tested with phenol red, same thing, it became colorless. I guess the chlorine oxidate the dye and destroys it? Btw, I then tested it with bromothymol blue and finaly got a result : the pH was between 1 and 6.

[Edited on 11-6-2014 by alexleyenda]

[Edited on 11-6-2014 by alexleyenda]
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[*] posted on 11-6-2014 at 03:24


How much sulphur trioxide would I need to dissolve in 100ml of 98% sulphuric acid to obtain 65% oleum (w/w)?

I assume I initially need to add enough to convert the outstanding 2% water to obtain 100% sulphuric acid?
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[*] posted on 14-6-2014 at 07:04


Is my hydrometer/specific gravity affected by altitude?



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[*] posted on 14-6-2014 at 07:30


Yes, but not by much. The density of air will be less, which will cause you to measure a slightly lower specific gravity (as some of your sample volume is air with a hydrometer).

Gravitational effects do not matter, as you are measuring relative specific gravity with a hydrometer.




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[*] posted on 14-6-2014 at 07:48


Quote: Originally posted by plastics  
How much sulphur trioxide would I need to dissolve in 100ml of 98% sulphuric acid to obtain 65% oleum (w/w)?

I assume I initially need to add enough to convert the outstanding 2% water to obtain 100% sulphuric acid?

You probably should not be making pyrosulfuric acid if you can't answer this question.




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[*] posted on 14-6-2014 at 08:13


Quote: Originally posted by Cheddite Cheese  
Yes, but not by much. The density of air will be less, which will cause you to measure a slightly lower specific gravity (as some of your sample volume is air with a hydrometer).

Gravitational effects do not matter, as you are measuring relative specific gravity with a hydrometer.


That was what I thought, but wanted some confirmation. Thanx cheddite.

Edit--@4000 feet above sea level here, twice as high as "home", Twentynine Palms

[Edited on 6-14-2014 by arkoma]




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[*] posted on 15-6-2014 at 12:25


Quote: Originally posted by Zyklonb  
Quote: Originally posted by plastics  
How much sulphur trioxide would I need to dissolve in 100ml of 98% sulphuric acid to obtain 65% oleum (w/w)?

I assume I initially need to add enough to convert the outstanding 2% water to obtain 100% sulphuric acid?

You probably should not be making pyrosulfuric acid if you can't answer this question.


OK smart arse. If you can't answer the question just keep quiet and stop filling the forum up with pointless shite.

Just for your delectation here is a picture of 120g SO3 sitting in a flask next to the tube furnace that generated it, waiting to be turned into oleum. Seeing as you think I am so stupid, perhaps I should just add 100ml warm water and see what happens?

So do you know the answer or not?

photo1.jpg - 633kB
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[*] posted on 15-6-2014 at 12:32


NO NO NO. Do not ever just add warm water (or any water at that) to that much SO3. That will send sulfuric acid everywhere and you won't get out unscathed.



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[*] posted on 15-6-2014 at 12:43


*Intensive sigh*
bismuthate, he was being sarcastic.
plastics, first calculate stoichiometrically how much SO3 is needed for that last 2% of water, then calculate how much additional SO3 you would need to add so that 65% of the H2SO4 is converted to oleum.
Funny thing is, I'm not sure of the chemical formula of oleum, so I can't help you there.




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