This is how I make my dichromate as well. Its easy but filtering and washing the chromium hydroxide is time consuming. The first time i did it i was actually really surprised that all the chromium hydroxide was consumed especially since I had used 3% h2o2. Great video man i really liked it and it was informative!
FYI, dichromate can be made directly, under fairly aggressive conditions: melt potassium chlorate and chloride with chromium oxide. O2 and Cl2 are given off, as the reaction turns deep blood-red, indicating molten dichromate. A clean steel or stainless crucible should be used (or probably hard glass or porcelain too), and the molten material should be poured into a very dry metal pan to cool, from which it will be loose and easy to work up. With KCl to balance, O2 release should be minimal. KOH can be added to absorb Cl2 as well, or balance for chromate instead. An excess of KClO3 should be used to account for catalytic breakdown (especially in a dirty or oxidized metal crucible, or if organics are present, etc.). It's been many years since I did this reaction so I don't recall exactly which way the balance works best, unfortunately. You'd probably want to oxidize your chromium metal to the oxide first though. Burning it in the same step might be a little too aggressive... ...That said, now I'm a little curious what chromium flash powder would look like. "Don't breathe this" indeed!
That's interesting. I always thought they just used cesium as the getter, because that's what just about everybody who explains it says. It's usually an offhand explanation, for example, while they're tinkering with a vacuum tube they might point out the getter material, and quickly mention it's cesium. Which chances are they probably just heard from somebody else, who heard it from someone else and so on without anyone actually checking. Thanks for clearing that up for me AND for the wonderful video. The effort you put into it really shows. Keep it up. =D Best regards from Canada.
But isn't it true then? I think that the getter is the deposit that gets the residual gas molecules, and this deposit can be metallic cesium. It might be that the name has transferred to the unflashed compounds and even the ring that is used to heat them, but when I refer to the getter I mean the metallic deposit.
Nice video, well done! Cr3+ is not nearly toxic as Cr(VI)... If you really want to be protected from carcinogens you should work with them outdoors or under a fumehood. Boiling the solutions will cary aerosols in the air - better wear a ffp2 or gas mask. Btw: In the EU enterprises are not allowed to work with chromates without REACH-license, so even monetized YT-channels do... So if I ever make a video about them, I would put I on a separate private channel... About the content: - If oxidized with H2O2, the oxidizer must be boiled off before the acidic converting to dichromate is done, otherwise the dichromate will decompose. - Better use sulfuric than hydrochloric acid to convert, because dichromate oxidizes HCl to chlorine! - Normally precipitations are made from solutions instead of adding a solid salt... 😉 Otherwise your Cs2Cr2O7 is evtl. contaminated with undissolved CsCl...
Thank you! The fact with the REACH license for YT Channels is very interesting, thanks! I boiled of the H2O2 before acidification. I figured the cesium chloride has such a high solubility in water, that it wouldn't be a problem.
Your product looks yellow instead of orange-red, more like caesium chromate than dichromate... Have you calculated the necessary amount of acid beforehand? New licenses are not made out anymore, on the contrary the existing have to be prolongated regularely - on application and chargeble of course... In fact it's a ban...
Because there was a lot of base left, calculating the amount of acid was not possible. I used the pH as an indication. When comparing the color with pictures on the internet it looks just like the dichromate. The chromate has a bright yellow color.
I've been trying to find out more about vacuum getter materials recently... so this is especially interesting. "or your dick suddenly falls off".... ZOIKS! I'll watch out for that. ;)
Very Nice. Cesium chloride is not cheap, I have some so I might make a gram or two of this. But why add cesium chloride as solid 🤔 I know it's very soluble but I thought it was better practice to disolve things before mixing
Yes, it would be best practice to dissolve the CsCl first. But I didn't want to add more water because it would mean I will also loose more of my dichromate. And due to the high solubility and because I washed the dichromate with water anyways, I decided to do it this way.
most youtube videos talking about non PG things: *skirts around the wording and algorithums* Advanced Tinkering: "yeh, i avoid messing with this stuff as i dont wana loose my ****"....
Generally one does not want chlorude ions around chromate at low pH. You risj the formation of chromyl chloride, CrO2Cl2 - which is todic as hell -and- volatile. Think sulfuric acid.
Man I hate it when chemicals make my dick fall off ;-) literal laugh out loud at that point. Do stay safe mate. Perhaps improvised fume hood with some inline extractor fans, ply wood and ducting? even if it's not perfect. generally getting the air moving the right direction is probably a good start.
I wasn't sure if people would like that joke. I will. Normally I am not working with toxic chemicals outside of a professional lab. My next videos will probably be about my new cryopump and a homemade vacuum chamber.
Hey!
1:56-2:16 nice camera angle 😁
Hi!
yes, I thought it looked cool :D.
I really like your channel btw!
@@AdvancedTinkering
Me too 😅
btw I'm going to post a new video about MnO3F (KMnO4+HSO3F) tomorrow!
Also neat to see the blue underneath -- the strongly reducing Cr(2+) I believe!
1:56 I love that blue color of chromium ii compounds
This is how I make my dichromate as well. Its easy but filtering and washing the chromium hydroxide is time consuming. The first time i did it i was actually really surprised that all the chromium hydroxide was consumed especially since I had used 3% h2o2. Great video man i really liked it and it was informative!
Thank you!
FYI, dichromate can be made directly, under fairly aggressive conditions: melt potassium chlorate and chloride with chromium oxide. O2 and Cl2 are given off, as the reaction turns deep blood-red, indicating molten dichromate. A clean steel or stainless crucible should be used (or probably hard glass or porcelain too), and the molten material should be poured into a very dry metal pan to cool, from which it will be loose and easy to work up.
With KCl to balance, O2 release should be minimal. KOH can be added to absorb Cl2 as well, or balance for chromate instead. An excess of KClO3 should be used to account for catalytic breakdown (especially in a dirty or oxidized metal crucible, or if organics are present, etc.). It's been many years since I did this reaction so I don't recall exactly which way the balance works best, unfortunately.
You'd probably want to oxidize your chromium metal to the oxide first though. Burning it in the same step might be a little too aggressive...
...That said, now I'm a little curious what chromium flash powder would look like. "Don't breathe this" indeed!
Fresnel lense, anyone?
That's interesting. I always thought they just used cesium as the getter, because that's what just about everybody who explains it says. It's usually an offhand explanation, for example, while they're tinkering with a vacuum tube they might point out the getter material, and quickly mention it's cesium. Which chances are they probably just heard from somebody else, who heard it from someone else and so on without anyone actually checking. Thanks for clearing that up for me AND for the wonderful video. The effort you put into it really shows. Keep it up. =D Best regards from Canada.
I think I even got the idea because I was thinking about how these getters work.
I appreciate hearing that you enjoyed the video! :)
But isn't it true then? I think that the getter is the deposit that gets the residual gas molecules, and this deposit can be metallic cesium. It might be that the name has transferred to the unflashed compounds and even the ring that is used to heat them, but when I refer to the getter I mean the metallic deposit.
Amazing video. Can you shpw your elements collection?
Fun stuff! Cheers!
Nice video, well done!
Cr3+ is not nearly toxic as Cr(VI)...
If you really want to be protected from carcinogens you should work with them outdoors or under a fumehood.
Boiling the solutions will cary aerosols in the air - better wear a ffp2 or gas mask.
Btw: In the EU enterprises are not allowed to work with chromates without REACH-license, so even monetized YT-channels do... So if I ever make a video about them, I would put I on a separate private channel...
About the content:
- If oxidized with H2O2, the oxidizer must be boiled off before the acidic converting to dichromate is done, otherwise the dichromate will decompose.
- Better use sulfuric than hydrochloric acid to convert, because dichromate oxidizes HCl to chlorine!
- Normally precipitations are made from solutions instead of adding a solid salt... 😉 Otherwise your Cs2Cr2O7 is evtl. contaminated with undissolved CsCl...
thank you. just wanted to mention similar things - especially the cancerogenic part. please.do.not.poison.yourself. all kind of cromates are mofos.
Thank you!
The fact with the REACH license for YT Channels is very interesting, thanks!
I boiled of the H2O2 before acidification. I figured the cesium chloride has such a high solubility in water, that it wouldn't be a problem.
Your product looks yellow instead of orange-red, more like caesium chromate than dichromate... Have you calculated the necessary amount of acid beforehand?
New licenses are not made out anymore, on the contrary the existing have to be prolongated regularely - on application and chargeble of course... In fact it's a ban...
Because there was a lot of base left, calculating the amount of acid was not possible. I used the pH as an indication.
When comparing the color with pictures on the internet it looks just like the dichromate. The chromate has a bright yellow color.
@@AdvancedTinkering Always a problem with the colours on video - they never look exactly like in real...
I would use CsOH to dissolve Cr(OH)3, then add an excess of H2O2, boil, and acidify with HCl. No Na+, no K+ right from the beginning.
I've been trying to find out more about vacuum getter materials recently... so this is especially interesting.
"or your dick suddenly falls off".... ZOIKS! I'll watch out for that. ;)
I use the same little bottles as well for storing samples
Very Nice. Cesium chloride is not cheap, I have some so I might make a gram or two of this. But why add cesium chloride as solid 🤔 I know it's very soluble but I thought it was better practice to disolve things before mixing
Yes, it would be best practice to dissolve the CsCl first. But I didn't want to add more water because it would mean I will also loose more of my dichromate. And due to the high solubility and because I washed the dichromate with water anyways, I decided to do it this way.
You can substitute titanium or aluminum to make your getter, helps to have the TI or Al in excess by about 2X.❤
3:46 Wouldn't you be creating chromium carbonate instead of hydroxide here? However both should work.
I think the only dichromate I've ever "handled" was Ammonium dichromate. We used to make volcanoes of it in chemistry classes.
most youtube videos talking about non PG things: *skirts around the wording and algorithums*
Advanced Tinkering: "yeh, i avoid messing with this stuff as i dont wana loose my ****"....
Please make a vdo on c-z group compound
caesium vapour was produced by reaction of caesium chromate with silicon, boron, or titanium as reducing agents
I have 200 g of sodium dichromate I do very cool plating with steel.
The reddish if you added cscl as solution it whould be better.
Generally one does not want chlorude ions around chromate at low pH. You risj the formation of chromyl chloride, CrO2Cl2 - which is todic as hell -and- volatile. Think sulfuric acid.
Man I hate it when chemicals make my dick fall off ;-) literal laugh out loud at that point.
Do stay safe mate.
Perhaps improvised fume hood with some inline extractor fans, ply wood and ducting? even if it's not perfect. generally getting the air moving the right direction is probably a good start.
I wasn't sure if people would like that joke.
I will. Normally I am not working with toxic chemicals outside of a professional lab. My next videos will probably be about my new cryopump and a homemade vacuum chamber.
3:52 hey ive done all steps up to this in this exact day because i just wanted chromium carbonate
It a very dangerous chemical as you said.
Make cesium hydroxide and dissolve stuff with it