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Detonationology
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[*] posted on 16-1-2016 at 08:42


Standard household ammonia is 3-7% NH4OH (NH3 in water). If one wished to increase the concentration of NH4OH in solution, I think the only way to do that would be to bubble more NH3 through the solution, which would react with the water. I have never heard of an NH4OH solution exceeding 27-30% (just under 1 mol per 100g H2O), probably because at such high concentrations, the ammonia gas and water are more favorable.

BTW, household ammonia contains surfactants. A 10% solution of surfactant-free janitorial ammonia can be found at ACE Hardware.




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[*] posted on 16-1-2016 at 09:20


Ammonium hydroxide is essentially an ammonia/water solution!

NH3 + H2O <─> NH4<sup>+</sup> OH<sup>−</sup>

The equilibrium is well to the right and NH3 escapes with evaporation and increase in temp. so that it cannot be dehydrated . . .

Gaseous ammonia may be added using an inverted funnel, with stirring, to increase concentration!

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[*] posted on 16-1-2016 at 10:55


I've long insisted that "ammonium hydroxide" is a misnomer for aqueous ammonia, used only because of Arrhenius' insistence that hydroxide was the only base in existence.



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[*] posted on 20-1-2016 at 17:40


Quote: Originally posted by hissingnoise  

Gaseous ammonia may be added using an inverted funnel, with stirring, to increase concentration!

...But heating the solution allows one to bubble ammonia gas into a vessel, so it at the very least a useful method to isolate ammonia.




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[*] posted on 21-1-2016 at 14:10
What kind of cotton comes in the top of medicine/pill bottles?


It has been some time since I've opened medicine bottles that had a large wad of cotton at the top of the container but I'm wondering if that kind of cotton has a name. It isn't cotton balls, swabs, pads or gauze (well I guess it could possibly be considered a type of gauze??). I'm guessing that it may be similar to what may be inside a tampon??:D

Anyway, I'm trying to find it in bags, rolls or whatever it may come in. I've tried the other types of cotton products and it doesn't work nearly as well as this for various uses. I've tried polyester fillling/stuffing but it doesn't work for what I need as the fibers aren't really absorbent in the same way and they don't retain "dirts" as well either.

Does anyone know what this stuff might be called or even where it may be gotten?
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[*] posted on 21-1-2016 at 16:44


usually cellulose i.e. cotton from agricultural sources.



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[*] posted on 23-1-2016 at 13:55


Does anyone know if this is true ?

So I was thinking about falling into a black hole few days ago. I summarized my thoughts that you should be able to see everything that will able to happen to the universe since when you're very close to black hole, time dialation start to significantly slow down, that you would never technically physically enter it since that also means the black hole will be evaporated from hawking radiation relative to the outside world ? Because as you close in onto a black hole, time relative to outside passes so slow, hawking radiation significantly happens faster, almost instantaneous.
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[*] posted on 23-1-2016 at 14:41


Quote: Originally posted by RogueRose  
It has been some time since I've opened medicine bottles that had a large wad of cotton at the top of the container but I'm wondering if that kind of cotton has a name. It isn't cotton balls, swabs, pads or gauze (well I guess it could possibly be considered a type of gauze??). I'm guessing that it may be similar to what may be inside a tampon??:D

Anyway, I'm trying to find it in bags, rolls or whatever it may come in. I've tried the other types of cotton products and it doesn't work nearly as well as this for various uses. I've tried polyester fillling/stuffing but it doesn't work for what I need as the fibers aren't really absorbent in the same way and they don't retain "dirts" as well either.

Does anyone know what this stuff might be called or even where it may be gotten?



"First, your downy plug might be cotton, but, equally likely it's rayon or polyester. Second, an organization called the United States Pharmacopoeia (USP), which has set quality standards for U.S. medicines for nearly 200 years, establishes criteria for that cotton. Not just anything goes."

Source: Why Is There Cotton In My Medicine Bottle? - Drugsdb.com http://www.drugsdb.com/blog/why-is-there-cotton-in-my-medici...
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[*] posted on 24-1-2016 at 18:50


Am I correct in thinking that this compound shows Cr in a +7 state?
http://cen.acs.org/articles/94/i4/Chromium-Nitrogen-Complex-...

The article shows a newly synthesised complex with single, double and triple bonds between Nitrogen and the same Chromium atom. But I am not really understanding how the molecule works. There appears to be an additional ligand that I was not expecting.


(Also in the news -- 1,1,2,2,tetranitroethane. Developed to possibly replace ammonium perchlorate but tends to go off with a bit of a bang.)




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[*] posted on 24-1-2016 at 19:31


@j_sum1 if you are still trying to separate the lithium from unknown sodium salts, a possibility is taking advantage of lithium carbonate's decreased solubility at higher temperatures in water [the industrial exploitation of this property is mentioned in passing here:https://en.m.wikipedia.org/wiki/Lithium_carbonate under properties and reactions, while specific numbers are given under properties] sorry I can't give any good references here I'm on my phone.

I would either add an excess of HCl to convert all salts to chloride, and then apply sodium carbonate and precipitate the lithium carbonate while hot, or boil a solution of the material to convert the hypochlorite to chlorate, precipitate the lithium carbonate with sodium carbonate and filter while hot, and add potassium chloride to obtain potassium chlorate aswell.

Depends what you have already (i.e. HCl or KCl) and if you could do with some KClO3 or Cl2.

Haven't performed anything like this myself.




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[*] posted on 24-1-2016 at 21:23


Thanks so much for that Li. (Appropriate post/username combo. Also, nice to spot another fellow countryman.)

It sounds like an exacting sort of a process, but a worthwhile sort of project for building up some skills. I might have to do it on a small scale. I lack the KCl to convert the whole bucket.

Incidentally, I attempted some iodometry with it the other day. (Or was it iodimetry -- I always conflate the two) It misbehaved and I did not get a result. So I am not sure what the "alkaline components" mentioned in the MSDS are. I had assumed NaOH as the most likely possibility. Whatever it was, it affected the formation of iodine-starch complex. I haven't figured out what was going on. I will have to study it a bit more closely before I have another attempt.




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[*] posted on 26-1-2016 at 16:26


Alright, how can I compress powdered charcoal into rods?



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[*] posted on 27-1-2016 at 12:38
MgOH from MgSO4 + Ammonia - different results than expected


I thought I would see how Mag Hydroxide would form from two different methods of preparation. In one beaker I mixed 100ml dH2O and 100ml ammonia solution then added about 60g of MgSO4 and stirred until dissolved. In another beaker I dissolved 60g of MgSO4 into 100ml dH2O and then added the 100ml ammonia.

The first beaker resulted in what seemed like crystals growing in solution, although not crystals - it was patchy formation of precipitate. The second beaker slowly turned from totally clear to opaque over about 20-30 mins.

After a few days of settling the second beaker had about 10x the amount of MgSo4 on the bottom of the beaker and it seemed much smoother (like how it is in milk of mag) the first beaker had what looked like sludge snotty white precipitate.

I looked at some videos about making MgOH this way and some say that 99% Isopropanol is needed to make the MgOH precipitate, while other pages say nothing about it.

Can anyone clear up why I might have gotten such different results from this and if the rubbing alcohol is actually needed?
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[*] posted on 28-1-2016 at 08:50


Quote: Originally posted by Velzee  
Alright, how can I compress powdered charcoal into rods?

You could always dissect a 6v battery to get four carbon rods. I don't think making them is very feasible, though.




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[*] posted on 28-1-2016 at 16:28


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):

e37M2t0.jpg - 108kB

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]




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[*] posted on 28-1-2016 at 18:39


Weight/density, if you can? That'd be a pretty good indicator. Is the streak light gray or dark gray?

In my experience, anthracite is a pretty brittle material, and powders all too easily.

If not, could it be graphite?




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[*] posted on 29-1-2016 at 00:01


Hi all, i have a patch of carbon stuck around the frosted joint. Is there anyway of removing it without using strong oxidant chemical? i tried scrubbing it, washing it with base, however it hasn't been very effective. I do not have the material to make chromic acid and do not want use a solution of sulfuric acid and h2o2. Thanks
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[*] posted on 29-1-2016 at 05:27


Quote: Originally posted by elementcollector1  
Weight/density, if you can? That'd be a pretty good indicator. Is the streak light gray or dark gray?

In my experience, anthracite is a pretty brittle material, and powders all too easily.

If not, could it be graphite?


I found the density to be around 1.24g/cc. I don't have anything suitable as a streak plate, so I can't tell you that.

[Edited on 1/29/2016 by Velzee]




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[*] posted on 29-1-2016 at 06:00


Quote: Originally posted by Velzee  
Quote: Originally posted by elementcollector1  
Weight/density, if you can? That'd be a pretty good indicator. Is the streak light gray or dark gray?

In my experience, anthracite is a pretty brittle material, and powders all too easily.

If not, could it be graphite?


I found the density to be around 1.24g/cc. I don't have anything suitable as a streak plate, so I can't tell you that.


Chip off a small chunk and see if you can get it to burn? Use a Bunsen or alcohol burner to heat it up sufficiently.

Carbon also reacts with concentrated nitric acid and concentrated NaOH.

[Edited on 29-1-2016 by blogfast25]




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[*] posted on 29-1-2016 at 10:33


Quote: Originally posted by blogfast25  
Quote: Originally posted by Velzee  
Quote: Originally posted by elementcollector1  
Weight/density, if you can? That'd be a pretty good indicator. Is the streak light gray or dark gray?

In my experience, anthracite is a pretty brittle material, and powders all too easily.

If not, could it be graphite?


I found the density to be around 1.24g/cc. I don't have anything suitable as a streak plate, so I can't tell you that.


Chip off a small chunk and see if you can get it to burn? Use a Bunsen or alcohol burner to heat it up sufficiently.

Carbon also reacts with concentrated nitric acid and concentrated NaOH.

[Edited on 29-1-2016 by blogfast25]


Chipping off a piece was really easy. Placing the piece in the flame of a stove top burner caused the edges to glow orange, and after a minute of heating, the glowing edge turned a white ashy color. The piece fell into stove top, but it never took a flame.




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[*] posted on 31-1-2016 at 08:44
Sodium ferrocyanide (yellow prussiate of soda)


Yellow prussiate of soda is a common anti-caking agent, but I can't find it for sale as a reagent anywhere. Am I missing something?
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[*] posted on 31-1-2016 at 08:50


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...

(Searching for things by their real names rather than using weird archaic ones sometimes leads to better results)




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[*] posted on 31-1-2016 at 09:18


http://www.elementalscientific.net/store/scripts/prodView.as...
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[*] posted on 31-1-2016 at 09:37
Sodium ferrocyanide


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.
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[*] posted on 31-1-2016 at 09:45


Quote: Originally posted by Velzee  


Chipping off a piece was really easy. Placing the piece in the flame of a stove top burner caused the edges to glow orange, and after a minute of heating, the glowing edge turned a white ashy color. The piece fell into stove top, but it never took a flame.


Sounds exactly like the anthracite I worked with - that stuff needs air influx and strong ignition (kerosene, etc.) to even light.




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