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Fery
National Hazard
Posts: 990
Registered: 27-8-2019
Location: Czechoslovakia
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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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vano
National Hazard
Posts: 661
Registered: 22-3-2019
Location: Georgia
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I think that too , but no more violuric acid, i used all.
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woelen
Super Administrator
Posts: 7976
Registered: 20-8-2005
Location: Netherlands
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Mood: interested
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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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vano
National Hazard
Posts: 661
Registered: 22-3-2019
Location: Georgia
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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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vano
National Hazard
Posts: 661
Registered: 22-3-2019
Location: Georgia
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Yes, some compounds are better stored than used. I think so because it has a different charm.
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woelen
Super Administrator
Posts: 7976
Registered: 20-8-2005
Location: Netherlands
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Mood: interested
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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
National Hazard
Posts: 645
Registered: 11-8-2015
Location: Missouri, USA
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Mood: No Mood
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| 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
Hazard to Others
Posts: 276
Registered: 31-8-2020
Location: America Lite
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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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soreff
Harmless
Posts: 12
Registered: 28-12-2014
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Mood: No Mood
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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
Hazard to Others
Posts: 276
Registered: 31-8-2020
Location: America Lite
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| 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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timescale
Harmless
Posts: 21
Registered: 12-9-2021
Location: USA
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Mood: Neurotic
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| 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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soreff
Harmless
Posts: 12
Registered: 28-12-2014
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| 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
Super Administrator
Posts: 7976
Registered: 20-8-2005
Location: Netherlands
Member Is Offline
Mood: interested
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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
National Hazard
Posts: 709
Registered: 28-3-2016
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Mood: No Mood
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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
Hazard to Self
Posts: 74
Registered: 11-7-2019
Location: Connecticut, USA
Member Is Offline
Mood: Moving out and setting up shop in my new chemistry hobbit hole
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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]
I am the one who boils to dryness, fear me...
H He Li B C(12,14) Na S Cl Mn Fe Cu Zn Ba Ag Sn I U(238)
"I'd rather die on my feet than live on my knees" -Emiliano Zapata
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yobbo II
National Hazard
Posts: 709
Registered: 28-3-2016
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Mood: No Mood
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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
Hazard to Others
Posts: 192
Registered: 4-7-2019
Location: West Coast USA
Member Is Offline
Mood: precipitatory
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| 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
International Hazard
Posts: 1110
Registered: 29-9-2019
Member Is Offline
Mood: Festive
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2100 L of argon!
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CharlieA
National Hazard
Posts: 645
Registered: 11-8-2015
Location: Missouri, USA
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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!) 
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B(a)P
International Hazard
Posts: 1110
Registered: 29-9-2019
Member Is Offline
Mood: Festive
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| 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!) |
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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pantone159
National Hazard
Posts: 586
Registered: 27-6-2006
Location: Austin, TX, USA
Member Is Offline
Mood: desperate for shade
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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
International Hazard
Posts: 1219
Registered: 15-4-2019
Location: Period 5, group 6
Member Is Offline
Mood: Volatile
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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
National Hazard
Posts: 586
Registered: 27-6-2006
Location: Austin, TX, USA
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Mood: desperate for shade
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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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pantone159
National Hazard
Posts: 586
Registered: 27-6-2006
Location: Austin, TX, USA
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Mood: desperate for shade
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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.
 
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ave369
Eastern European Lady of Mad Science
Posts: 596
Registered: 8-7-2015
Location: No Location
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Mood: No Mood
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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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