Making Bromine

Рет қаралды 11,681

Күн бұрын

In this video I discuss and make some of the beautiful but very dangerous chemical bromine.
Bromine is one of only two elements that is a liquid at STP, and behaves much like chlorine sharing many of the same hazards. I plan to use this chemical in the future for a variety of projects that I'll likely link here when they come out.
PLEASE READ: I do not recommend anyone but trained professionals attempt this process due to several significant hazards associated with the synthesis of this element. Bromine is as lethal as chlorine, except due to its much greater density it is capable of much more easily reaching high concentrations in air. It also sinks due to its very high density and can accumulate in low areas.
Bromine can only be safely stored in ampules, under strong reducing agents, and OUTSIDE.
Post-Release Notes:
1. I think I hate the little formation mechanism I drew now even more than I hated it when I drew it. That said, don't take that mechanism as an absolute representation of how the reaction happens. It was mostly meant to illustrate generally how one peroxide molecule could oxidize two HBr molecules.
2. The final product still contains an appreciable volume of sulfuric acid due to the drying process. Based on solubility data I could find it should be less than 1mL, which is fine for my purposes but if you'd need 100% pure bromine another distillation is necessary.
#chemistry #science #hydrogen #gas #elements #fire #chemical #industury #color

Пікірлер: 68

@Relatablename 4 ай бұрын

Bromine drizzled over schnitzel goes so hard

@MattsProductions 4 ай бұрын

So true, and i use sodium bromide mixer with breadcrumbs for breading

@nilamotk 4 ай бұрын

Hold the open end of the test tube in a drill gently. Run the drill slowly. Hold the torch in 1 spot near the chuck and let the weight of the test tube body stretch the ampule. You will be left with near perfect ampules.

@integral_chemistry 4 ай бұрын

That is brilliant! I can't believe I've never thought of that, absolutely going to write that down and give it a shot next time.

@Uncharted_Escapes09 4 ай бұрын

Always a good day when Apoptosis posts a chemistry video!

@integral_chemistry 4 ай бұрын

Thank you so much 😁 trying to be consistent with saturday/Sunday

@Samonie67 4 ай бұрын

i've personally had great success storing bromine at -20C inside a simple amber glass jar placed inside a jam jar surrounded by a bit of thiosulphate. it's stored in a dedicated freezer for chemistry and from measurements I did I've only lost about 200mg's of bromine over the course of 3 years.

@integral_chemistry 4 ай бұрын

Yeah I probably should have taken more advantage of low temp for this project in general. Dedicated lab freezer is definitely #1 on my wish list, and they aren't really expensive I'm just so limited on space sadly. BTW 200mg is actually even lower than I'd expect, basically a margin of error after 3 years

@Samonie67 4 ай бұрын

@integral_chemistry yea I figure it's probably condensation or something thats causing errors

@kibnob 3 ай бұрын

Thanks for including cleanup info

@demandred1957 4 ай бұрын

"Today I thought it would be a good idea, to get added to another -list- for watching a cool video".. lolol

@mattheide2775 4 ай бұрын

My favorite class in highschool was chemistry and Mr. Anderson loved to demonstrate reactions under the Vent hood😊 Thank you for the video ❤

@integral_chemistry 4 ай бұрын

No problem at all 😁 I always love hearing from the rare person who actually liked chemistry class

@mattheide2775 4 ай бұрын

@@integral_chemistry That was 32 years ago and I learned the metric system, covalent bonding and how to run Cross Country from Mr. Anderson. Great Educators make great people. Thank you for educating me.

@196Stefan2 4 ай бұрын

3:45 It also works with MnO2 as a cheap and easily obtainable, relatively mild oxydizing agent. In many countries, KMnO4 and H202 in a higher concentration than 12 % are no more legally available. K2Cr2O7 as a highly toxic CMR-substance and KBr03 as a carcinogen and Chlorates are totally out of reach. Despite Chlorine is used for the production of Bromine in a technical scale, it has another downside for "home-grown" Bromine: It is probably physically soluble into Bromine (without the formation of ClBr), which leads to a chlorine-contaminated Bromine.

@andrews.4780 4 ай бұрын

Yayyy bro finally participated in a bromine vid

@ChemicalEuphoria 4 ай бұрын

i used manganese dioxide instead of hydrogen peroxide, and it works like a charm!

@CassidyGentry-lq8qf 4 ай бұрын

This is so amazing!! Thank you for your hard work and dedication 🤩

@ssmith5048 4 ай бұрын

you can use sand in your heating element to take care of the size mismatch to get more even heat distribution

@jerrysanchez5453 4 ай бұрын

This might have the highest yield I've seen for a bromine synthesis

@integral_chemistry 4 ай бұрын

It did go remarkably well! I do think there is a bit of sulfuric acid still hanging out in the final product, and I should probably distill that out. Based on solubility data I could find it should be less than a milliliter, but still enough to note.

@jerrysanchez5453 4 ай бұрын

@@integral_chemistry still a fantastic yield. Great job! Love to see more videos

@experimental_chemistry 4 ай бұрын

A quite safe and easy to handle methode to make small amounts of bromine water on demand is to mix and acidify separately prepared and stored solutions of bromide and bromate in a stoichiometric ratio: bromine in aqueous solution is formed then by a comproportionation reaction.

@2tommyrad 4 ай бұрын

Always great content, thanks.

@integral_chemistry 4 ай бұрын

Thanks man! Very glad to hear it

@Psychx_ 4 ай бұрын

You can also use Bromine to titrate the amount of unsaturated fatty acids in vegetable oil.

@lucazsy 4 ай бұрын

If bromine is your second favorite element, what's the first? Would you make an element tier's list?

@integral_chemistry 4 ай бұрын

I've actually wanted to do that for ages but I've worried the "tier list" trend was dead. I think I will just go ahead and do that regardless and just ignore any haters lol

@andersjjensen 4 ай бұрын

@@integral_chemistry Screw the haters! If you have funny commentary for a tier-list, hit us with it!

@experimental_chemistry 4 ай бұрын

My favorite method is just using cheap but fresh sodium persulfate in access, mixed with bromide and water, so not even sulfuric acid is needed. The yield is very high and the bromine quite pure (accept for a little water). Acid dryed bromine contains significant amounts of sulfuric acid and has to be redistilled before ampouled. Borosilicate ampoules can only be sealed tightly with an acetylene torch. With propane commercial ampoules made from lime-soda glass should be used instead. Bromine water has to be stored in brownglass bottles with a ptfe sealed lid put into a second container with a little thiosulfate solution. Its shelf life isn't longer than a year. To neutralize bromine I recommend an slighly alkaline solution of sulfite (must be prepared freshly because it's not storable).

@integral_chemistry 4 ай бұрын

Thank you for the great notes as always! The big one here that stands out to me is the sulfuric acid in the final product, I hadn't even really considered it being more than a slight impurity. Before I go through the dangerous headache of redistillation, do you mean "significant" by analytical standards, or significant enough that it would seriously interfere with organic reactions? I intend to use the bromine for bromobenzene as well as the direct bromination of a few other organics and while I feel the amount of sulfuric acid present is low enough to not interfere, I feel you'd know better. Also very interested that persulfate can be used without any acid at all. I figured it would make a fine oxidizer but I just figured acidification was always necessary. Very good to know, although it is weirdly expensive in the US for some reason.

@experimental_chemistry 4 ай бұрын

@@integral_chemistry Sodium persulfate is the last strong oxidizer you can get here with nearly no restrictions and cheap as well (about 12-15 euros per kilo). It can be used with potassium bromide in a 1:1 stoichiometric ratio (or better in a 2:1 access if you are not sure how fresh the stuff is). This is much more efficient than using legal 15 % sulfuric acid (4 euros per litre) or 12 % hydrogen peroxide (12 Euro per litre). If residues of conc. sulfuric acid interfere in reactions depends on what you are using bromine for. In OC it's surely better than having water in it, while for the reaction between Al and Br2 a little water helps starting it. To be on the safe side it's better to redistill it. The effort isn't that huge and the distillation is one of the fastest I know - much faster than the synthesis itself beforehand. Here in the EU things are much more complicated: we have to replace conc. sulfuric acid by anhydrous CaCl2 or Na2SO4 as drying agent now. But I have to admit that I never felt comfortable with shaking these both substances from hell in a separatory funnel anyways (in those times when conc. sulfuric acid still was permitted). So I stirred them magnetically with a small stir bar instead while cooling the test tube in an ice bath, and separated bromine and acid afterwards. By the way: for bromine you need special bended pipettes. The easiest way to fill the ampoules is using the separatory funnel and a simple glass funnel in between both for it. All three items should be clamped sepatetely in a stand during the filling process for safety reasons because this is the most dangerous part of the whole process - respirator, goggles and thick chemical gloves are absolutely manditory here. All steps of the process have to be carried out outdoors or under a fumehood.

@zenongranatnik8370 4 ай бұрын

@@experimental_chemistry By persulfate you mean reagent grade one or is the oxone pool disinfectant enough?

@experimental_chemistry 4 ай бұрын

@@zenongranatnik8370 These are different substances: pool oxone is the potassium salt of the peroxomonosulfuric acid. It's not suited to oxidise bromide to bromine. Persulfate is the sodium salt of the peroxodisulfuric acid, which is a strong oxidizer and mainly used for etching circuit boards.Technical grade is sufficient because you will never get 100 % stuff anyways. It always contains a decent amount of plain sodium sulfate formed by slow decomposition. Persulfate has no long shelf life (at most few years if stored cool and dark). Therefore it should never be stored in tightly sealed containers because otherwise they might burst under the pressure of oxygen gas released. They need a screw cap with an equilation velve instead.

@experimental_chemistry 4 ай бұрын

@@zenongranatnik8370 It's not the same: oxone used for pools is the triple salt of potassium biperoxomonosulfate, bisulfate and sulfate. Persulfate used for etching circuit boards is sodium peroxodisulfate (Na2S2O8). Technical grade is o.k., it's never pure anyways because of partial self decomposition.

@markedis5902 4 ай бұрын

Phosphorus pentachloride…. Sounds fun

@200-b8k 4 ай бұрын

Good video

@morescodesup2087 3 ай бұрын

The coolest substance for a darklord’s moat.

@gutefragen5427 4 ай бұрын

nice Video!

@snoowbrigade 4 ай бұрын

epic halogen time

@markedis5902 4 ай бұрын

Yellow chemistry

@DangerousLab 4 ай бұрын

It is so interesting to see pee pads in every video, even against bromine it still works very well! Btw, it seems to be quite dangerous to use pee pads to contain any flaming reaction.

@integral_chemistry 4 ай бұрын

Oh yeah they work fantastic! The only issue is they are somewhat expensive, at least for how often I replace them. If my projects weren't being recorded I'd probably switch them out less frequently so the price wouldn't be as bad. And yeah they don't offer much protection against flame, but they are fire retardant so they themselves won't burn (at least this specific brand). Acetone also tears them up.

@soldier821-u6o 4 ай бұрын

Red

@UncleRus 4 ай бұрын

Great training video for mephedrone cooks

@Patrisumbro 4 ай бұрын

That mechanism made the Ochem teacher in me scream, great video otherwise.

@integral_chemistry 4 ай бұрын

Yeah in retrospect I feel I should have left it out and just left it as a simple reaction 😅 I also co-taught ochem for a stint (not as a professor, it was a paid peer instructor role) but yeah looking at this mechanism I made enrages me, I just can't make the inorganic ones make sense. In any case thank you! Glad you liked the vid otherwise 😁

@calebcoulthard3607 4 ай бұрын

did this one year ago in organic chemistry lab

@larsschneider5806 4 ай бұрын

Do you think, that the reaction would be almost as efficient or doable as yours, if there was a 12% H2O2 solution used?

@integral_chemistry 4 ай бұрын

Yeah probably, the only difference is you'd end up with more water in the reaction flask which would hold onto a bit more bromine. Probably not a crazy amount though, especially at higher heat.

@uoli7770 4 ай бұрын

Yo i just wanna recommend manganese heptoxide. Its scary but you can prepare it in situ and its a lot cheaper. You can use MnO2 instead of permanganate. I'm pretty sure its how Prussian blue did it so its definitely possible in a rat fest lab like his. Edit: nvm it was amateur chemistry, but its definitely possible especially if the highest concentration H2O2 you can get is 12% like me.

@libalj 4 ай бұрын

Spicy ninja smoke balls

@Psychx_ 4 ай бұрын

Are the test tubes you use for ampule making also made out of borosilicate or just regular glass?

@RiehlScience 4 ай бұрын

They’re Pyrex, so high quality borosilicate.

@realedna 4 ай бұрын

1:57 Your reaction mechanism and explanation thereof are less than ideal and also a bit confusing. 😛 (it's not a displacement reaction, but clearly a redox reaction and the hydrogen/proton doesn't transport electrons) In the first 2 steps you can regard hydrogen bromide (pKa = -9) as being fully dissociated (you also said that). So H+ and Br- will likely act as separate species here. You show Br- with 7 e- and a minus-sign, so do you mean a Br- or a Br-radical/atom (neutral)? In step 3 it should at least be 2 radicals/atoms forming a Br2 molecule and there are no negative charges involved. Well, due to step 2 it seems you actually mean Br-, which is pretty wrong for step 1 and 3. My proposed mechanism: 1. H2O2 + Br- --> HOBr + OH(-) (pK 2 OH would have only pK=9.8=unlikely/slow; radical-formation maybe somewhat more likely due to heat in any case though] 2. OH- + H+ --> H2O (pK = -14, see "Water" on Wiki) 3. HOBr + H+ + Br- --> Br2 + H2O (pK = -8.1, see "Bromine" on Wiki) H2O2 is highly more likely to decompose into radicals, if it gets a single electron (see "Fenton's reagent"). Here Br and OH can form hypobromous acid directly, which is much more stable than free radicals. A negative pK here means, that the reaction equilibrium lies on the right side of the equation. Step 1 stems from the fact, that OH + Br- --> BrOH- (pK~-10 at low pH), which is basically a Br bound to an OH-. Also HOBr and OH- being easily quenched in acidic bromide solution (step 2 & 3) is what drives the reaction forward.

@realedna 4 ай бұрын

According to Nature-articles from 1949 "The Bromine Cation, Br+, and its Reactions" and 1950 "An Oxidation Involving the Hydroxyl Cation" in strong mineral acid environments (conc. H2SO4) HOBr can form Br+ (bromine cation) and H2O2 can even form OH+ (hydroxyl cation). Those species can act as strong oxidizing agents, but they might play only a minor role here. They would probably only form Br2 from Br+ + Br- or HOBr from HO+ and Br- anyways.

@integral_chemistry 4 ай бұрын

Sorry I'll definitely reply to this more in depth later (or in the vid description) but I 100% agree with you. My mechanism there is a nightmare to any real chemist (including myself) and I honestly should have left it out and just included the simple equation. To answer your questions yes the Bromines with 7 electrons around them are meant to represent bromine radicals (which I've seen as Br*, but I'm not sure how to formally notate a radical), they definitely aren't meant to represent bromide ions but again I actually never learned how that should be drawn. You are almost certainly right about this mechanism proceeding through hypobromous acid and peroxide radicals. My issue is my professional background is organic chem so I think I defaulted to making this into something like an organic mechanism which flatly doesn't work either. Final result is an incorrect mechanism that is dreadful to both organic and inorganic chemists.. I think it's nearly time I compile all my mistakes into a single video because I make at least one big one per post 😅 PS: Thank you very much for the feedback, lord knows I need help with my inorganic chem.. especially these damn nonmetals.

@realedna 4 ай бұрын

@@integral_chemistry Sorry, I hoped it wouldn't come across as disrespectful correction, but merely as a discussion about the actual mechanism and to clarify confusing parts. Because you included it in the video, it actually sparked my interest and led me to investigate and learn about it. So I'm glad you did! 😃👍 Now I also understand what you meant to describe. You proposed a fully radical mechanism, yet you really drew all those radicals confusingly. So an OH (hydroxyl radical) can be written without anything or with a single centered dot (single electron) added. But it's not charged and hence no minus-sign. Similarly with bromine atoms/radicals you could just use Br /w or /wo a dot. Also drawing all those electron-pairs as lines instead of double-dots is less confusing IMHO (or just don't draw them at all - for clarity in terms of minimalism). So your equations and explanations make more sense now. Your eq 1 is actually my eq 1+2 combined, if you would have shown, that HO- and Br-radicals are likely to bond together as HOBr.

@realedna 4 ай бұрын

@@integral_chemistry Your step 2 symbolizes, what you described as affinity of atoms for each other. But this form of electron-transport via an hydrogen atom is not realistic. As it's a redox reaction it's interesting to understand how the electron-transfer actually happens. It can either be a single- or double-electron transfer in 1 step. You showed H2O2 decomposing homolytically in step 1, but that is highly unlikely (pKa=10). It might be that it is rather heterolytically split into OH+ and OH-, because of the highly acidic environment: 1. HOOH + H+ --> HOO(+)H2 2. HOO(+)H2 --> HO(+)OH2 3. HO(+)OH2 + Br- --> HOBr + H2O So a proton can attack an electron-pair on an oxygen of H2O2 and bond with it (as it also often does in organic mechanisms). That induces a positive charge onto that oxygen, which is likely to shift somewhat to the other oxygen (so this is where the electron-shift between the halfs of H2O2 happens). Then a bromide ion can attack as a nukleophil and split the bond between the oxygen atoms, letting water form directly as a side-product/leaving-group. The rest is then just the certain equilibrium of HOBr in HBr-solution, which produces Br2 easily.