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Author: Subject: Latest chemical order?
Fery
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[*] posted on 5-9-2021 at 23:57


Here in CZ I was able to buy thoriated tungsten welding electrodes (TIG), they contain upto 4% of ThO2, but W must be dissolved first to obtain ThO2. Nobody uses these electrodes today because of choices of less toxic compounds available. The shop offered me a discount and they found 2 more electrodes in stock so they contacted me later whether I wouldn't like to buy also these extra electrodes which were not listed in eshop (I added to cart all pieces available in their eshop system so they correctly presumed I would like to buy everything they have).



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[*] posted on 6-9-2021 at 00:15


Quote: Originally posted by woelen  
A really nice one would be thorium violurate ;)

I think that too:) , but no more violuric acid, i used all.




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woelen
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[*] posted on 6-9-2021 at 00:17


I actually do have some thorium metal, but I never did any experiments with that. It was donated to me, more than 10 years ago and I put it on my website:

https://woelen.homescience.net/science/chem/compounds/thoriu...

I will not break this sample. Although it is not really nice looking, it is interesting to have around. Only years, after I received the sample, I began to realize how rare this must be.




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[*] posted on 6-9-2021 at 00:21


Quote: Originally posted by Fery  
Here in CZ I was able to buy thoriated tungsten welding electrodes (TIG), they contain upto 4% of ThO2, but W must be dissolved first to obtain ThO2. Nobody uses these electrodes today because of choices of less toxic compounds available. The shop offered me a discount and they found 2 more electrodes in stock so they contacted me later whether I wouldn't like to buy also these extra electrodes which were not listed in eshop (I added to cart all pieces available in their eshop system so they correctly presumed I would like to buy everything they have).


I have lots of Czechoslovakian chemicals, almost all is analytical reagent, maybe they also produced uranium and thorium salts for analytical chemistry. In those days, their salts were not considered as dangerous.




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[*] posted on 6-9-2021 at 00:23


Quote: Originally posted by woelen  
I actually do have some thorium metal, but I never did any experiments with that. It was donated to me, more than 10 years ago and I put it on my website:

https://woelen.homescience.net/science/chem/compounds/thoriu...

I will not break this sample. Although it is not really nice looking, it is interesting to have around. Only years, after I received the sample, I began to realize how rare this must be.


Yes, some compounds are better stored than used. I think so because it has a different charm.




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woelen
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[*] posted on 29-10-2021 at 07:08


I purchased an ozone generator tube, with a separate adjustable power supply (3 ... 40 W high frequency high voltage) and a separate quartz tube for conversion. A little air pump (5 liter per minute) is delivered with the ozone generator, but I'll probably not use that. I have an oxygen generator, which can generate 1 liter per hour at 93% O2, or 2 liter per hour at 70% O2.

The tube apparently is designed for a somewhat higher flow of 5 liter per minute, but probably lower flows will work as well, if you crank down the power output of the high voltage generator.

With the ozone I want to do interesting experiments. Only small amounts of ozone can be made with this device (max 3 grams per hour, according to specification, but I do not believe that figure). Probably less than 1 gram per hour, but it should be enough for small scale ozone experiments.




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CharlieA
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[*] posted on 29-10-2021 at 15:23


Quote: Originally posted by woelen  
......

With the ozone I want to do interesting experiments. Only small amounts of ozone can be made.....


Please keep us posted; I am sure that your experiments will be very interesting.
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itsallgoodjames
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[*] posted on 3-11-2021 at 16:17


20211103_200249.jpg - 2.3MB

My chemcraft order has arrived!
50g iodine
10g HgCl2
100g NaI
100g sodium metal




Nuclear physics is neat. It's a shame it's so regulated...

Now that I think about it, that's probably a good thing. Still annoying though.
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[*] posted on 9-11-2021 at 11:35
CS2 ?


Can anyone suggest a supplier of CS2 that will ship small quantities
(around 10ml - 100ml) to individuals in the United States? I'd like to
grow sulfur crystals by slow evaporation, and, as far as I know, CS2
is a much better solvent for S8 than anything else. Yeah, I know it is
carcinogenic - I'd be doing the evaporation outside.
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itsallgoodjames
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[*] posted on 9-11-2021 at 11:43


Quote: Originally posted by soreff  
Can anyone suggest a supplier of CS2 that will ship small quantities
(around 10ml - 100ml) to individuals in the United States? I'd like to
grow sulfur crystals by slow evaporation, and, as far as I know, CS2
is a much better solvent for S8 than anything else. Yeah, I know it is
carcinogenic - I'd be doing the evaporation outside.


Provided you don't mind buying 500ml, chemsavers has it.

If you want a smaller quantity, it may be best to message mario840 or chemship1978. They're both from Poland (if I recall correctly), but shipping of 100ml probably won't be too expensive.

The main danger of CS2 isn't that it's carcinogenic, it's the flammability. CS2 is very volatile, and it's vapors have an autoignition point of around 100ºC.




Nuclear physics is neat. It's a shame it's so regulated...

Now that I think about it, that's probably a good thing. Still annoying though.
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[*] posted on 9-11-2021 at 11:57


Quote: Originally posted by soreff  
Can anyone suggest a supplier of CS2 that will ship small quantities
(around 10ml - 100ml) to individuals in the United States?


Chemsavers lists CS2 on their website, but when I asked about it I was told it's on the "only real labs with commercial addresses can buy" list. :(

LabDirect is the only domestic seller I know of: https://www.labdirectllc.com/product/CS2/107




Est-il une beauté aussi belle que le rêve ?
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[*] posted on 9-11-2021 at 11:58


Quote: Originally posted by itsallgoodjames  
Quote: Originally posted by soreff  
Can anyone suggest a supplier of CS2 that will ship small quantities
(around 10ml - 100ml) to individuals in the United States? I'd like to
grow sulfur crystals by slow evaporation, and, as far as I know, CS2
is a much better solvent for S8 than anything else. Yeah, I know it is
carcinogenic - I'd be doing the evaporation outside.


Provided you don't mind buying 500ml, chemsavers has it.

If you want a smaller quantity, it may be best to message mario840 or chemship1978. They're both from Poland (if I recall correctly), but shipping of 100ml probably won't be too expensive.

The main danger of CS2 isn't that it's carcinogenic, it's the flammability. CS2 is very volatile, and it's vapors have an autoignition point of around 100ºC.


Many Thanks!

Best wishes,
-Jeff
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woelen
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[*] posted on 12-12-2021 at 11:19


I ordered 4 small bottles of CH2Cl2 (4 x 500 ml), now that it still is possible to obtain this. It looks like the sale of DCM to private individuals is going to be forbidden in the EU. De oplosmiddelspecialist in the Netherlands already does not sell it to belgian residents anymore, and sale to dutch residents seems to be limited to 300 ml.
I do not use DCM a lot, with these 4 bottles I will have enough for many years to come. DCM is not something you can easily make at home, making it is much harder than making chloroform. That's why I ordered it.




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yobbo II
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[*] posted on 16-12-2021 at 10:27



You can purchase DCM + Methanol paint remover, 5L, in car accessory shops for about 30 Pounds in the UK.
It is for 'professionial' use only.

Yob
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aab18011
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[*] posted on 17-12-2021 at 06:44


New chemical shipment came in last week,

-500g of an old phenol bottle from TCI that is easily 8 years old but still unopened (was cheap as hell, but I need some ideas on what to do with it)
-50g of Oleum (30%)
-100mL THF
-250mL of EtOH (99.99% food grade and kosher, who knew it would or could be kosher)
-50g of Sn
-100g of Sodium Azide
-250mL of Bromobenzene
-50mL of Acetic anhydride
-250mL of 38% H2O2
-100g of NaNO2
-75g of Iodine (elemental)

Also, LabDirect is the best place to go in my opinion. I have dealt with others but Richard C. (The owner) is a great guy and actually loves hobby chemistry. He has frequently given me discounts and will always help you find the right price. I usually email him with a cas number and the use for it. Usually if its water sensitive I tell him and he will find a cheap supplier. He has even helped me reduce the price of overseas stock. Im 100% sure you can find a cheap CS2 supplier through him.


[Edited on 12-17-2021 by aab18011]

[Edited on 12-17-2021 by aab18011]




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H He Li B C(12,14) Na S Cl Mn Fe Cu Zn Ba Ag Sn I U(238)
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yobbo II
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[*] posted on 21-12-2021 at 16:47



In relation to dichloromethane, this stuff contains it.

https://www.ebay.co.uk/itm/384345107507?hash=item597cc0ec33:...

Langlow strip away pro.


Yob
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MidLifeChemist
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[*] posted on 1-1-2022 at 19:37


Quote: Originally posted by soreff  
Can anyone suggest a supplier of CS2 that will ship small quantities
(around 10ml - 100ml) to individuals in the United States? I'd like to
grow sulfur crystals by slow evaporation, and, as far as I know, CS2
is a much better solvent for S8 than anything else. Yeah, I know it is
carcinogenic - I'd be doing the evaporation outside.


Hot Xylene should also work, and it is easy to get
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B(a)P
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[*] posted on 20-1-2022 at 13:21


2100 L of argon!


PXL_20220120_204350875.jpg - 4.5MB
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CharlieA
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[*] posted on 20-1-2022 at 14:34


It seems to me that the volume of that cylinder is somewhat less than 2100L. Is that the volume that the argon would have at 1 atm Pressure? I'm just confused (not that is an unusual state for me!) :D
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[*] posted on 20-1-2022 at 14:58


Quote: Originally posted by CharlieA  
It seems to me that the volume of that cylinder is somewhat less than 2100L. Is that the volume that the argon would have at 1 atm Pressure? I'm just confused (not that is an unusual state for me!) :D


You are correct, it is a D size cylinder. It holds compressed argon that is the equivalent of 2100 L at STP.
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[*] posted on 20-1-2022 at 15:21


Bromocresol purple, powder, water soluble, 1g.
'Bromothymol blue', Na salt, powder, WS, 5g.
Fructose, purified, 25g.
D-glucose, anhydrous, reagent grade, 100g.
Lithium chloride, granular, lab grade, 100g.
Oxalic acid 2-hydrate, crystal, ACS, 125g.
Phenol red, Na salt, WS, indicator powder, O.R., 5g.
Sodium phosphate, dibasic, anhydrous, ACS, 100g.
Sodium tungstate, granular, reagent grade, 25g.
pH paper, 1-12, #50.

I suspect that my 'bromothymol blue' is actually bromophenol blue. When I dissolve some of this in water, it makes a rather strange and interesting colored solution. When I look though a large thickness of solution, the color is red. But looking at a small thickness, the color is green instead. (And little bits of the solution that dry on the sides of the vial are blue.) This optical behavior seems to be characteristic of bromophenol blue, but not of bromothymol blue.

I intend to prepare some pH buffers to evaluate which compound this really is, the yellow-blue transition point is different by about 3 pH units between the two.
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Bedlasky
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[*] posted on 20-1-2022 at 20:42


Bromophenol blue should be blue in water. Bromothymol blue green. Bromothymol blue in conc. HCl should give red colouration (at least according to wiki).






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pantone159
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[*] posted on 21-1-2022 at 07:05


I think I have the sodium salt of whatever indicator I have, so it is, I believe, in a concentrated solution at the midpoint of the color change, so green. (Sort of, the same green solution is actually red if you look through a thick section of the solution. It is rather interesting.) With much more dilution with H2O I get a slightly greenish yellow solution.

I do see a color change at very low pH: A 2.7 mol/kg solution of HCl gave a red-orange color, very distinct from the yellow color, and a 2.0 mol/kg solution of H2SO4 also gives a red-orange color, perhaps not as strong colored as the HCl one. In both of these cases, some solid precipitate seems to form.

I wondered about the wikipedia notes on the red color, I find no other references besides that photo, and the red color change is disputed in the wikipedia talk section. But my indicator does indeed change to a reddish color at pH < 0.

I think I will try and prepare a pH 5.4 solution. Bromophenol blue and bromocresol blue should be fully blue at this pH, while bromophenol blue should be fully yellow.

The wikipedia entry for bromophenol blue states the following, which is consistent with my indicator:
In solution at pH 3.6 (in the middle of the transition range of this pH indicator) obtained by dissolution in water without any pH adjustment, bromophenol blue has a characteristic green red colour, where the apparent colour shifts depending on the concentration and/or path length through which the solution is observed. This phenomenon is called dichromatic color.[7] Bromophenol blue is the substance with the highest known value of Kreft's dichromaticity index.[8] This means it has the largest change in colour hue, when the thickness or concentration of observed sample increases or decreases.

[Edited on 21-1-2022 by pantone159]
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[*] posted on 2-2-2022 at 12:34


I conclude that my indicator is indeed bromothymol blue, as claimed by the seller, and not bromophenol blue, as I had suspected.

I prepared some pH buffer solutions, using preparations from CRC handbook, to cover the range of bromothymol blue, bromophenol blue, and bromocresol green, and added some of the indicator to each. The colors observed match that for bromothymol blue, and not the other two indicators.

The actual vs expected result for these indicators:
pH actual bromothymol blue bromophenol blue bromocresol green
< 3 yellow yellow yellow yellow
3.0 yellow yellow yellow [edge] yellow
3.8 yellow yellow green [mid] yellow [edge]
4.6 yellow yellow blue [edge] green [mid]
5.4 yellow yellow blue blue [edge]
6.0 yellow (slt green?) yellow [edge] blue blue
6.8 green green [mid] blue blue
7.6 blue (slt green?) blue [edge] blue blue
9.2 blue blue blue blue

However, a strong solution of this indicator does show the dichromatic effect which is very pronounced for bromophenol blue. The second photo shows the indicator solution in transmitted light: When looking through a thick portion of the solution, the color is red. But when looking at a thin portion, i.e. the meniscus at the surface, the color is green. My photo is not great but the different colors are visible.


bromothymol_blue_03.jpg - 123kB bromothymol_blue_05.jpg - 73kB
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[*] posted on 13-2-2022 at 09:36


Recently, my age-old interest in ferrates was piqued by a recent purchase: a mixture of potassium permanganate and sodium ferrate. This mixture is sold OTC in my country because pure potassium permanganate is a listed chemical.

The product looks like a gray powder (sodium ferrate) with purple-black crystals (potassium permanganate). It does not appear possible to physically separate them. Upon dissolving, it forms a reddish-purple solution, purpler than pure permanganate but redder than pure ferrate.

If sulfuric acid is added to the solution, oxygen is evolved, and the color shifts to pure permanganate purple as the ferrate decomposes.

I've performed some experiments with this mixture. It does oxidize CoCl2 to Co2O3 and Cl2. It also precipitates barium ferrate with a soluble barium salt, but I failed at isolating barium ferrate because I tried to use a fritted glass filter and the gel-like precipitate clogged it.




Smells like ammonia....
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