Added: 3 months ago
From: UC235
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  • What is the purity of the final product?

  • you sir make grate videos.

    can you make one on the prepperation of chloral and chlorobenzene for the synthesis of DDT?

  • @surplusdriller No, on the grounds that chloral is a US list IV controlled substance and making it (for any purpose) would be a criminal offense with the video being all the needed evidence to convict.

    On the other hand, I have found a way to sidestep the need for chloral. p-chlorobenzaldehyde can react with chloroform in alkaline conditions to give 4-chloro-(2,2,2-trichloro-1-hy­droxyethyl)benzene, the intermediate in the DDT synthesis. This with H2SO4 and chlorobenzene would give DDT.

  • does anyone actually realise what this shit is used for haha

  • @gunny0488 I've been waiting for a stupid comment for a while. So far, I've used it to recrystallize 5-carboxypentyltriphenylphosph­onium bromide and for azeotropic drying during a fischer esterification. Did you know that gasoline is used for getting high if you're poor and vengefully burning other people's vehicles/houses/etc? The point is that almost everything has negative and positive uses and chloroform's ability to knock people out is rather exaggerated.

  • @UC235 fair enough didn't really need an essay to get your point across

  • How do you figure that the Cl-Cl bond has any partial charges? Did you mean the Cl-OH?

    (Since Cl and Cl obviously have the same electronegativities, shouldn't they chare the electrons equally?)

  • @sk8erpunk1933 Diatomic halogens are particularly susceptible to induced dipoles caused by close proximity of a polar molecule or an ion (like the acetone enolate in particular). Relative to molecules such as H2 or hydrocarbons, they are much more easily polarized.

  • im trying to get me a distiation kit. if the kit is good im gonna get it but i need to know if it is a good kit. thx

  • i have a question. is borosilicate glass 3.3 (pyrex) good glass for distilation. here is the kit

    ebay(DOT)com/itm/New-Organic-L­ab-Glassware-Kit-Joint-size-24­-40-/250814649120?pt=LH_Defaul­tDomain_0&hash=item3a65b7d320

  • Keep the long videos...

  • Your videos are some of the best synthesis videos I've seen so far. I like how you get into detail with the mechanisms, and mention the chemical's uses.

  • I appreciate the depth you go into with the mechanism

  • "I can already smell the chloroform" <- Best line.

  • @cobrasniper555 that should be a catch fraze for chuck norise 

  • Haha, and there I was, cooling the mix with ice and wasting over an hour adding acetone. Great work! After a couple semesters of class, I really need to update my chloroform video... lots of goofs in that one :/

    I love your videos. Do you mail order your glass?

  • @zhmapper I am a discriminating ebay shopper. I have also had good experiences with united glass tech, though they are a bit more expensive. How is the yield with the ice-chilled mix and slow addition? I'd expect it to be a bit better, but it's a lot of effort unless the yield improves dramatically. Even then, the bleach is pretty cheap (though you'd need $30USD to make a liter of chloroform this way) and the effort required is nearly zero.

  • @UC235 My yield was very poor considering that I hadn't the forethought to let the mixture settle for more than 30 minutes before decanting off the waste, which was still considerably turbid at the time. Thanks for the glassware advice. Have you built your lab over time or did you order the majority at once to get started?

  • @zhmapper I built up over time. It was very frustrating at first when I had shiny new 1-neck RB flasks, but no other nice glassware. A condenser followed shortly, and then a slew of adapters to make a simple distillation setup. I quickly came to preps where I needed some piece of glass that I didn't have and couldn't improvise. Cue soxhlet extractors, fractionating columns, dean stark traps, fritted bubblers, multi-neck flasks, lots and lots of stoppers, an addition funnel, etc.

  • Question: about how long of a shelf-life does typical reagent grade (sigma) chloroform have before it turns acidic? assuming the solvent is pre-treated as you mentioned, will it last years?

  • @staratsx That would depend very much so on storage conditions. Keeping it cold and in the dark (which is why amber glass is preferred) should slow down degradation. Additionally, oxygen is needed for the conversion to phosgene. If the bottle is brand new from the supplier and sealed, it may very well be fine, even after a dozen years or so. If the bottle is opened frequently for use, the shelf life will be much shorter.

  • @UC235 yeah it's stored in amber glass, but i should probably assume the presence of breakdown products just to err on the side of caution.

  • As an aspiring chemist, I find your videos VERY helpful. Thank you so much for all the effort you put in to the videos, it really does show when someone is passionate about their craft. It might sound a little corny, but I actually think it's rather inspiring. :)

  • I have observed some CCL4 in the bottom of the chloroform layer. How is it formed?

  • @ytmachx I'm not sure what you mean by "in the bottom of the chloroform layer." To me, that sounds like you had an additional phase, which is confusing. Tet should be miscible with chloroform. If you mean that you fractionally distilled the product and found a substance coming over at 76.7C, then I would suspect nucleophilic attack of CCl3- on Cl-OH or Cl2. Apparently the free radical halogenation of chloroform is difficult at best.

  • @UC235 It's just that I see some heavier clear liquid in the bottom of the receiver after distillation. After removing it from the chloroform it smells like CCL4. (I'm using acetone,H2O and calcium hypochlorite)

  • Keep the vids flowing buddy!

  • Thank you very much for your very interesting chemistry videos. They are very, very, very, good.

  • I agree with toothpick, keep the longer videos. I enjoy the explanations. I'm pretty new to organic chemistry and I enjoy knowledge.

  • If you left it long enough, would you get more of a yield? say more then a day? in the last part you said "when standing with alkaline solution, chloroform hydrolyzes and is converted to 3eq. of chloride and one of formate, how would you separate the 2? Sodium Formate would be useful to make Formic Acid... One of the best Chloroform videos i have see, explains it well for anyone wanting to do this one at home :) keep up the awesome work :) i like longer videos... explains it more in detail :D

  • @toothpick93 All the chloroform is generated probably within the first few minutes after mixing the reactants, which is why it gets so hot. The standing period is to let the droplets of chloroform settle into a layer. If you look at reactionfactory's chloroform video, the water they pour off is cloudy from little drops of chloroform that haven't settled. With regards to formate, you'd be looking at extremely dilute solutions in excess NaOH. I reccomend the oxalic acid/glycerol route instead.

  • @UC235 If u done that but in large scale, would it be a good way to make Sodium Formate? I reckon you could make a great video on doing the oxalic acid/glycerol method, with ur skills and knowledge, u could really make a good video i bet :) but u don't have too if u don't want to or have no use for it :)

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