I tend to have real difficulty picturing what I’m supposed to be doing, and what the desired end result of a lab experiment is when I’m just reading it out of a lab manual. There have been times when I’ve read through the procedure three or four times over, and I still can’t get my head around it. Being able to see what goes on is so helpful for me.
Thank you professor Dave for bringing this experiment series. Not everyone has easy access to experimental apparatus which makes experimental chemistry far fetched. But your playlist is helping a lot with that problem.
every time i watch one of these videos, i'm just in awe of the processes and try to picture how people were able to figure these things out. this is just 1 small process, to acheive a single result that is itself only 1 step in a much larger process. what do all flat earth and intelligent design people think it's just a ridiculously complicated process to conceal the fact that the earth is 1000 years old and flat
I am compelled to express my profound admiration for your exceptional pedagogical skills. Your ability to distill and simplify concept is very commendable. As a holder of a Bachelor of Science degree in Industrial chemistry, with a deep-seated passion, I will consider it a remarkable opportunity to be mentored by someone of your caliber. Thanks for all your Videos
I would like to add a few things: first, never do a closed system distillation, as the vapors can build pressure and cause an explosion. It is best do to a distillation in a fume hood, to prevent injuries from occuring.
This is very beneficial because it is hard to visualize the experiment by reading the lab manual. So then you feel lost when its lab day but this helps me prepare. Thank you for posting.
Literally me with orgo lab in uni. Went in first day(we’re only given the procedure for use, not how to set up the contraption) and expects us to know every piece of glassware and how to connect them.
Slightly more complex than I thought, but interesting. The condenser must be why people get wet cloth when trying to distill in suboptimal conditions i.e. survival/survival education
Destilação simples usa os pontos de ebulição dos componentes da mistura aplicada em misturas miscíveis, em que há uma grande diferença entre os pontos de ebulição dos componentes equipamentos fonte de calor (manta de aquecimento balão de fundo redondo adaptador com três saídas se for usar um termômetro. caso não, pode usar um conector com formato de cotovelo) condensador outro conector duas mangueiras recipiente coletor para o destilado alguns suportes universais e garras passo a passo (sem termômetro) Colocamos o frasco de fundo redondo sob a fonte de calor e nele colocamos o conector deixamos o sistema mais seguro firmando ele com garras ao suporte universal no gargalo do balão colocamos o condensador conectado ao conector, deixando-o inclinado para que o destilado escorra do outro lado, conectamos outro conector e asseguramos ele com outra garra (aprendi a colocar garras para segurar o condensador também, acho recomendável) conectamos as mangueiras ao condensador, tomando cuidado para que as mangueiras não richicoteiem e quebrem alguma coisa a água entra pelo buraco de baixo (mangueira que deve ser conectada à uma torneira) e sai pelo de cima (mangueira que deve ser colocada numa pia) notas:a substância que se vaporiza (que é destilada) é a que tem o ponto de fusão mais baixo para que a mistura não borbulhe muito dentro do balão, colocamos pérolas de porcelana dentro do recipiente só acione a fonte de calor quando tiver certeza que tudo está bem conectado cuide para que apenas uma substância seja evaporada
Just to nitpick a bit, the dye is left behind not because of solubility but because it has low volatility compared to isopropyl alcohol. Color tells you nothing about the purity of the distillate in this case.
I should have said that clarity per se tells you little about the purity. If dye did get over, it probably would be carried physically by a "bump" (an explosive burst of vapor), which would carry over water and any other impurities too. Stirring and boiling chips reduce the chance bumping.
Yeah, I was confused about that part. With my understanding of vapourization, the dye would have to vapourize at a lower boiling point than the water to get carried over. Considering that Dave does not disclose the boiling point of the dye, that means that we do not know the boiling point of the dye. The dye could have a much higher boiling point than the water and if that is the case, it would say nothing about the purity of the isopropyl alchohol. For a dye to work as an indicator of purity it would have to have the same boiling point as the water or lower. Please correct me if I am wrong.
Hi Dave, great video, as always, how do you disinfect the glass vessel / plastic tubes after each use to remove any remnants that may have stuck on the surface? Thanks
Depends on whether or not you were using water or organic solvents. If water was used rinse with deionized water, if organic solvents were used rinse with acetone.
Also the times when I’ve done this and graphed it, certain dyes will yield a boiling point that’s different from th alcohol. So our graph ended up with 3 flat lines instead of 2 (one for the alcohol & another for water bp)
Thank you so much for this tutorial. 4/5 stars. One point off because the white coat camouflaged the setup at times. And thank you for providing the name “grease” instead of … I’d rather not say.
May I please ask a (stupid?) question? Why the inlet of water has to be from the bottom of the condenser, and the outlet of water at the top of the condenser? Can I not swap them round, and if so, why is that? Thank you kindly for your reply.
@@ProfessorDaveExplains no offence professor, but why wouldn't it completely fill the condenser if it the water was running in the downwards direction? 🤔
@@ProfessorDaveExplains sorry, that doesn't quite resonate- if it comes at the top then gravity will make it fall at the bottom - and it would fill the condenser completely. So then - still my valid question- why feeding from the bottom to top?
@@ProfessorDaveExplains besides - I can see if it fills the condenser completely and if it didn't I would increase the water flow, still doesn't quite explain the requirement of having the inlet down and outlet up
I like your videos, but i thought Isoprop is forming an azeotropic mix with water, similar to other alcoholes with water. This means you cannot separate them completely by standard distillation.
does isopropyl alcohol have a lower boiling point bc of the alkane branching ? as both have vanderwaals forces as well as hydrogen bonding forces. like is there a specific label to this is asked on a quiz? per organic chem the more branched a chain the lower the boiling point unless other intermolecular forces r present .
I always see lab videos run tap water through the condenser and into a drain, whereas home experimenters tend to setup a reservoir with ice water and a pump to recirculate it Obv with the latter, it depends on how practical it is to keep the condenser inlet water cool, and ice takes resources to produce too Running it from the tap to the drain just seems so wasteful, I'm wondering what the practical tradeoffs are. I'm sure the vapor temp and distillation time come into play
When I do distillations, I use a recirculating pump to run my condenser exactly as you suggested. The extra power used by the pump is minimal - it's a little brushless submersible pump, running from an old wifi router power supply, using less than 10 watts at 12 volts. It can raise water to a maximum vertical height above the pump of 1.5 metres, so it is entirely practical to have the distillation setup on a table and a bucket of water on the floor as the reservoir. Unless you plan on running a distillation literally all day continuously, you don't really need any ice. I can run my distillation setup for about 6 hours, enough to distil a couple of litres of "solvent", and the water in the bucket just gets slightly warm after that time. Perhaps if the bucket was insulated and had a lid on it, the water would get significantly warmer and might need some ice. But as soon as the water in the bucket gets appreciably warm, evaporation from the surface tends to cool it down, so it reaches an equilibrium after a few hours, with the heat delivered from the condenser being dissipated into the air in the room by evaporation. You can even enhance this effect by mounting a small fan on the edge of the bucket to blow air across the surface of the water.
have you seen the siphon pot vaccuum coffee makers? They are literally all this, except it burps and goes right back to where it started. all over again.
7:30 is this graph right? How are we getting distillate before the solution reaches it's boiling point (at like.. 30°C??) It should start with 0, and stay 0 until the inflection point at 78°C at which we start collecting.. should then very slowly rise untill we get all the alcohol out (like on the graph). The presence of alcolhol lowerse bp of initial solution below 100C obviously, but the BP is slowly rising as the alcohol content decreases. Evaporation is also what's 'taking' away the heat applied, preventing the temperature from increasing linearly.. Am I missing something?
Hey! I know it’s not really your area of expertise but I’d love a discussion on the idea of advanced ancient civilizations that guys like Graham Hancock push. It gets a lot of attention and is just straight up misinformation.
Hi Prof Dave - may I check my understanding of the distillation process, please? (I am not a chemist, but I am a distiller - this is legal in NZ, where I live, so I have some practical experience and I have endeavoured to learn all I can about the process, but I certainly do not have a rigorous understanding of things.) This explanation [1:07] makes it sound as if the trick is to simply pick a temperature above the BP of the lower liquid in solution - but my understanding is that when you have two liquids mixed, they will produce a solution with a BP that is somewhere between the two individual BPs, relative/proportional to the ratio of the mixture - that's Raoult's Law, right? And it is not linear, but has a negative or positive deviation from a line between the two BPs? So to distill a mixture, you need to heat the liquid to the BP of the *mixture* so that when the mixture boils you get vapours coming off that you can readily distill. If we don't heat the mixture to it's BP, only evaporation vapours will come off the liquid, which is not at a very fast rate, right? Something else you said I didn't understand [6:20] how can we heat the liquid mixture past it's BP? It isn't like in a liquid with two substances there is some of the stuff boiling off at one temperature and we can keep heating it to the next BP where the other substance starts coming off as gas, that violates Raoult's Law. At the BP of the mixture, all the energy is going into the latent heat of vapourisation to turn it into gas, yes? Like, you cannot heat water past 100C because the energy goes into converting water into steam. At a 50:50 mix of alcohol and water, that'd have a BP of a bit over 81degreesC? zenodo.org/record/1513542/files/article.pdf So it should not be possible to heat that mixture beyond ~81C, any excess energy will go into making gases. The temperature of the liquid will eventually rise, but only as the ratio of alcohol:water changes affecting the BP (so a 10:90 solution will be boiling at about 86C, yes?) [6:04] What we definitely want to do is control the rate of heating so we keep the boiling to a low rate to avoid violent boiling and an excessive vapour rate that exceeds the ability of the condenser to knock down the vapours into liquid. We want enough energy going into the liquid to keep the liquid boiling gently and pushing out those gases, but we are controlling the amount of energy being put into the process of vapourisation to keep control of the rate of the process - not preventing the temperature of the liquid from rising past the BP - yes? Also [1:15], my understanding is that the vapour coming off the liquid mixture is not purely composed of the substance with the lower BP, but is itself a mix of the two solutions, but in different proportions to the original mixture, with the vapour ratio having a higher component of the more volatile substance than the ratio in the liquid. chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Equilibria/Physical_Equilibria/Raoults_Law_and_Ideal_Mixtures_of_Liquids The result is a liquid with a reducing mix ratio, but not purely 'leaving behind' the liquid with the higher BP, right? I think this is what you note at [7:31]. For data collection, [7:08] another possibility that would have been interesting would have been to periodically sample the distillate, measuring the proportion of water and alcohol in the distillate using a refractometer - it would have shown the earliest distillate samples had a higher proportion of alcohol than later samples, due to the reducing alcohol-water ratio in the flask. And [1:20] because the vapours coming off the boiling liquid are a mixture of the substances, just in a different ratio than in the original liquid, when the vapours are collected and cooled, the distillate is not pure but just purer than the original liquid mixture - yes? So to work toward purity, the distillate needs to be re-distilled, because the distillate will boil off vapours that have a higher ratio of the more volatile substance...? So at [8:25] the distillate cannot really be said to be isopropyl alcohol separated from the mixture, we can really only say that it is purer than the initial mixture - right? The clarity of the distillate - could this be due to the low volatility of the dye, meaning the proportions of the dye in the vapour mix is negligible? It surely cannot be used as a reliable indicator of the proportion of the water to alcohol mix in the distillate...? I understand that it is sometimes necessary to make simplifications to explain concepts, but I do think that the way I was taught chemistry at school (including this idea of the lower BP substance boiling off first) means I misunderstood things that I had to unlearn later. I don't think it is too hard to understand the idea that a mixture takes on a BP somewhere between the BP of the components. Also, I don't think it hurts for us to learn early on that processes like distillation are not 'perfect', we don't get 'pure' anything out the other end, that is a useful thing to know. And WHY that is the case might be something that is left for a more advanced class, but at least we aren't left with misunderstandings from oversimplifications? I mean, it isn't necessary to over-complicate things with explanations of azeotropes and why this means you cannot actually distill 100% pure alcohol from an alcohol-water solution, simple is good, but too simple isn't great, surely? Oh, - and a big thank you for the free public education work you do.
I have found this physical chemistry lesson by Steven Stuart to be very informative: ua-cam.com/video/ZV6J3UgV31I/v-deo.html but it would be great to have a video like yours that explains this behaviour in a simpler fashion for the sort of audience you were aiming at.
You have a good understanding of the situation, but distillation CAN achieve complete separation of volatile compounds. If the b.p. difference is high enough and there are no azeotropes, essentially one liquid boils first then the other. If the difference is small, you still can achieve separation with a fractionating column or, using better technology, with a spinning band distillation apparatus. This happens because you have thousands of theoretical plates: it is like redistilling a thousand times in one shot. I have separated liquids which differed in b.p. by 1-2 degrees, each >99% pure. Bottom line: this video refers to the practice of distillation, and I do not think it wanted to touch on theory, which is extremely complex. There may be other videos explaining that.
@@galileog8945 if the substances have a negative deviation from Raoult's Law, then yes, purity is possible. Those are rare mixtures though. For all positive deviations from Raoult's Law, even those without azeotropes, many theoretical plates achieves an approximation of purity (like >99%) not actual purity.
@@JeremyTaylorNZ When you separate substances by distillation, I do not think you need to know if there are deviations from Raoult's law. Complete separation is possible, and the more theoretical plates you have, the more complete it is. Practically speaking, 99% is pretty good, but it is not a limit. "Approximation of purity" has no meaning in chemistry.
@@galileog8945 I should have said 'strong deviations such that there is an azeotrope' not just 'deviations but it is in fact important and relevant to whether you can produce what anyone would call a pure substance. For instance, because ETOH and water have a min-boiling azeotrope, it is impossible for a distillate with even a billion theoretical plates to get beyond 95.6% alcohol by weight - which is a long way from 'purity', where a chemist has the capability of measuring contamination down to ppm ua-cam.com/video/VO5P7PT8gI8/v-deo.html
Hi my name is John Castor I want to find out if there was any way that I could get some help with help with getting some lab glassware because I am very short on that I'm trying to start off a small business of extracting lemonade and extracting the pepper extracting different extracts of different species of plants thank you very much I would very much appreciate that thank you
Hey, I dont know if this is where I would say this but this might be a good debunk type video topic. There is a company called Solex LLC that sells these sham "frequency" type products. Typical quantum mysticism word salad, they can apparently "scan your body" and "balance your frequencies", just a whole lot of tripe. However, their products are geared toward people with serious diseases, and claim to be able to effortlessly cure anything from cerebral palsy to cancer. (This includes a close family friend of mine, who our mom bought some of their products for.) They also charge absurd prices for things that are incredibly easy and cheap to produce, going so far as selling unmodified tablets that you can buy for a few hundred dollars, for over a thousand dollars. This is a horrible company that is personally hurting people I care about, so if this seems like a good topic to tear apart, that would be amazing. Thanks!
@@ProfessorDaveExplains Not being argumentative and this video is good. But, what can be achieved by this experiment? My apologies. I'm just not in the know. Only curious Thanks
Nuh-uh! A round-bottom flask? It is obviously a flat-bottom flask, open your eyes! When you take into consideration the refraction of the light within the container it is obvious that the surface is flat. Nice try NASA shill but the coriolis effect is not possible on your model. The curvature is simply artificial because of the fish eye effect of our eyes. Here is 100% proof that it is not a round bottom flask, but a flat bottom flask: If you were to cut it in half, why does it look like a *dome* ???? OPEN YOUR EYES Diffraction. Reverse refraction. Angular perspective. rising eye level. Def leppard. diminishing visibility level. I wet my pants last night. All proof against your "science"
I tend to have real difficulty picturing what I’m supposed to be doing, and what the desired end result of a lab experiment is when I’m just reading it out of a lab manual. There have been times when I’ve read through the procedure three or four times over, and I still can’t get my head around it. Being able to see what goes on is so helpful for me.
Thank you professor Dave for bringing this experiment series. Not everyone has easy access to experimental apparatus which makes experimental chemistry far fetched. But your playlist is helping a lot with that problem.
I haven't done chemistry like this since finishing A-Levels. Simple, logical, repeatable. Wish I did more.
Matter is anything that occupies space and has mass.
You should be a comedian
Getting to be.
@@SnubMonk My jokes are nothing compared to your autobiography.
@@indigofenrir7236 At least you admitted what you said was a joke
@@SnubMonk I never said my comment was one of my jokes. You on the other hand just proved your lapse in reasoning.
I LOVE DISTILLATION AND EVAPORATING LIQUIDS TO CONDENSE THEM AND MAKE THE LIQUIDS PURE
Avoid drugs
@@danicajohnson2664 😂
The best part is drinking that distilled potato juice. What? I didn’t say anything. 😮
@@danicajohnson2664 drugs are bad mmkkkkkk
every time i watch one of these videos, i'm just in awe of the processes and try to picture how people were able to figure these things out. this is just 1 small process, to acheive a single result that is itself only 1 step in a much larger process. what do all flat earth and intelligent design people think it's just a ridiculously complicated process to conceal the fact that the earth is 1000 years old and flat
I am compelled to express my profound admiration for your exceptional pedagogical skills. Your ability to distill and simplify concept is very commendable. As a holder of a Bachelor of Science degree in Industrial chemistry, with a deep-seated passion, I will consider it a remarkable opportunity to be mentored by someone of your caliber. Thanks for all your Videos
10 points to Ravenclaw for the use of the word "pedagogical".
I would like to add a few things: first, never do a closed system distillation, as the vapors can build pressure and cause an explosion. It is best do to a distillation in a fume hood, to prevent injuries from occuring.
Do you know why the vacuum adapter was used?
How do you extract scent from anything? To duplicate it to create a formula to reproduce.
This is very beneficial because it is hard to visualize the experiment by reading the lab manual. So then you feel lost when its lab day but this helps me prepare. Thank you for posting.
I know right
how do teachers expect us to imagine this in our heads lol, this video made me actually understand what was happening
Literally me with orgo lab in uni. Went in first day(we’re only given the procedure for use, not how to set up the contraption) and expects us to know every piece of glassware and how to connect them.
@@bigsmall2842 HAHAHA
Slightly more complex than I thought, but interesting. The condenser must be why people get wet cloth when trying to distill in suboptimal conditions i.e. survival/survival education
Thank you, professor Dave! You are a great chemistry teacher!
Professor can you devote your time into making a playlist for logic, set theory and proofs? Superb explanations thx
I have some of that in my math playlist. Logic is coming in my philosophy playlist.
Thank you proffeser dave
This channel is one of my favourites
Ahh taking me back to my organic chem 101 days! 😏
Destilação simples
usa os pontos de ebulição dos componentes da mistura
aplicada em misturas miscíveis, em que há uma grande diferença entre os pontos de ebulição dos componentes
equipamentos
fonte de calor (manta de aquecimento
balão de fundo redondo
adaptador com três saídas se for usar um termômetro. caso não, pode usar um conector com formato de cotovelo)
condensador
outro conector
duas mangueiras
recipiente coletor para o destilado
alguns suportes universais e garras
passo a passo (sem termômetro)
Colocamos o frasco de fundo redondo sob a fonte de calor e nele colocamos o conector
deixamos o sistema mais seguro firmando ele com garras ao suporte universal no gargalo do balão
colocamos o condensador conectado ao conector, deixando-o inclinado para que o destilado escorra
do outro lado, conectamos outro conector e asseguramos ele com outra garra
(aprendi a colocar garras para segurar o condensador também, acho recomendável)
conectamos as mangueiras ao condensador, tomando cuidado para que as mangueiras não richicoteiem e quebrem alguma coisa
a água entra pelo buraco de baixo (mangueira que deve ser conectada à uma torneira) e sai pelo de cima (mangueira que deve ser colocada numa pia)
notas:a substância que se vaporiza (que é destilada) é a que tem o ponto de fusão mais baixo
para que a mistura não borbulhe muito dentro do balão, colocamos pérolas de porcelana dentro do recipiente
só acione a fonte de calor quando tiver certeza que tudo está bem conectado
cuide para que apenas uma substância seja evaporada
Lab technique is just like handwriting if you are anxious or ocd you don't do your experimental well. All true statements about me.
Thank You. Dipping My Toe In. Happy Just Learning! Thanks!
Just to nitpick a bit, the dye is left behind not because of solubility but because it has low volatility compared to isopropyl alcohol. Color tells you nothing about the purity of the distillate in this case.
Fair enough, so if dye were to get into the alcohol, this doesn't mean that water necessary took a trip too. Thanks for the insight.
I should have said that clarity per se tells you little about the purity. If dye did get over, it probably would be carried physically by a "bump" (an explosive burst of vapor), which would carry over water and any other impurities too. Stirring and boiling chips reduce the chance bumping.
Yeah, I was confused about that part. With my understanding of vapourization, the dye would have to vapourize at a lower boiling point than the water to get carried over. Considering that Dave does not disclose the boiling point of the dye, that means that we do not know the boiling point of the dye. The dye could have a much higher boiling point than the water and if that is the case, it would say nothing about the purity of the isopropyl alchohol. For a dye to work as an indicator of purity it would have to have the same boiling point as the water or lower. Please correct me if I am wrong.
@@Xerrash As an artist, this is so damn interesting, especially when I'm high.
Hi Dave, great video, as always, how do you disinfect the glass vessel / plastic tubes after each use to remove any remnants that may have stuck on the surface?
Thanks
Depends on whether or not you were using water or organic solvents. If water was used rinse with deionized water, if organic solvents were used rinse with acetone.
@@maxrosen169 thanks so much :)
Also the times when I’ve done this and graphed it, certain dyes will yield a boiling point that’s different from th alcohol. So our graph ended up with 3 flat lines instead of 2 (one for the alcohol & another for water bp)
thank you my friend
I really like science projects bt how l separate water from alcohol
Please do steam distillation and fractional distillation sir , so many are having doubts in those concepts in understanding
Thank you Professor Dave!
Could you please make a video on distillation of an essential oil? In this case we should use fractional distillation?
Do you have the equipment for distillation.? Let me tag you in a video that teaches to distill an essential oil.
Can't tag you on you tube I don't know how I can share it with you.
2:21 what is that round bottom support made out of?
Thanks Professor!
This is a wonderful video! Thank you!
so does distilling tap water result in 2 sollutions one of H2O and the other of whatever minerals of the water? is distilling it multiple times best?
thank you professor dave
Can you recommend a good source for basic equipment to get started?
Is the round bottom glass used so there's more surface area of the liquid to speed up evaporation?
Thank you so much for this tutorial. 4/5 stars. One point off because the white coat camouflaged the setup at times. And thank you for providing the name “grease” instead of … I’d rather not say.
Thanks, Professor Dave! I would just like to know where you found the materials used in the video for the distillation setup. Thank you! :)
thank you so much! it was really useful!
Waiting for more videos
May I please ask a (stupid?) question? Why the inlet of water has to be from the bottom of the condenser, and the outlet of water at the top of the condenser? Can I not swap them round, and if so, why is that? Thank you kindly for your reply.
It's to ensure that it completely fills the condenser.
@@ProfessorDaveExplains no offence professor, but why wouldn't it completely fill the condenser if it the water was running in the downwards direction? 🤔
@@aniawo5119 It might not, it could fill only the lower half and fall directly into the other hose.
@@ProfessorDaveExplains sorry, that doesn't quite resonate- if it comes at the top then gravity will make it fall at the bottom - and it would fill the condenser completely. So then - still my valid question- why feeding from the bottom to top?
@@ProfessorDaveExplains besides - I can see if it fills the condenser completely and if it didn't I would increase the water flow, still doesn't quite explain the requirement of having the inlet down and outlet up
Water might still evaporate at a temperature above 60.. At 80 degree how does the system ensure pure alcohol is collected without any traces of water?
I'm from family of distillers and we have a spiral condenser with active carbon filter in our lab ;P
THANKS FOR BEING MY DAD POP 🥹🥹🥹
Well done!
Heyy Prof, it's possible to desalinate seawater through distillation, right?
yes
nice explanation,
we use simple distillation when there is a big difference in their boiling point right
I like your videos, but i thought Isoprop is forming an azeotropic mix with water, similar to other alcoholes with water. This means you cannot separate them completely by standard distillation.
Wouldn't it be safer when performed within a fume hood?
How do you extract scent from anything? To duplicate it to create a formula to reproduce.
do they sell propane and propane acessories ? 😁
Parts of simple distillation
does isopropyl alcohol have a lower boiling point bc of the alkane branching ? as both have vanderwaals forces as well as hydrogen bonding forces. like is there a specific label to this is asked on a quiz? per organic chem the more branched a chain the lower the boiling point unless other intermolecular forces r present .
I always see lab videos run tap water through the condenser and into a drain, whereas home experimenters tend to setup a reservoir with ice water and a pump to recirculate it
Obv with the latter, it depends on how practical it is to keep the condenser inlet water cool, and ice takes resources to produce too
Running it from the tap to the drain just seems so wasteful, I'm wondering what the practical tradeoffs are. I'm sure the vapor temp and distillation time come into play
When I do distillations, I use a recirculating pump to run my condenser exactly as you suggested. The extra power used by the pump is minimal - it's a little brushless submersible pump, running from an old wifi router power supply, using less than 10 watts at 12 volts. It can raise water to a maximum vertical height above the pump of 1.5 metres, so it is entirely practical to have the distillation setup on a table and a bucket of water on the floor as the reservoir.
Unless you plan on running a distillation literally all day continuously, you don't really need any ice. I can run my distillation setup for about 6 hours, enough to distil a couple of litres of "solvent", and the water in the bucket just gets slightly warm after that time. Perhaps if the bucket was insulated and had a lid on it, the water would get significantly warmer and might need some ice. But as soon as the water in the bucket gets appreciably warm, evaporation from the surface tends to cool it down, so it reaches an equilibrium after a few hours, with the heat delivered from the condenser being dissipated into the air in the room by evaporation. You can even enhance this effect by mounting a small fan on the edge of the bucket to blow air across the surface of the water.
More of this
have you seen the siphon pot vaccuum coffee makers? They are literally all this, except it burps and goes right back to where it started. all over again.
Thanks brother
7:30 is this graph right? How are we getting distillate before the solution reaches it's boiling point (at like.. 30°C??) It should start with 0, and stay 0 until the inflection point at 78°C at which we start collecting.. should then very slowly rise untill we get all the alcohol out (like on the graph). The presence of alcolhol lowerse bp of initial solution below 100C obviously, but the BP is slowly rising as the alcohol content decreases. Evaporation is also what's 'taking' away the heat applied, preventing the temperature from increasing linearly..
Am I missing something?
Good stuff!
Yo this is my professor
thank you
Hey! I know it’s not really your area of expertise but I’d love a discussion on the idea of advanced ancient civilizations that guys like Graham Hancock push. It gets a lot of attention and is just straight up misinformation.
Distillation makes whisky possible. Ah, single malt.
Hi Prof Dave - may I check my understanding of the distillation process, please? (I am not a chemist, but I am a distiller - this is legal in NZ, where I live, so I have some practical experience and I have endeavoured to learn all I can about the process, but I certainly do not have a rigorous understanding of things.) This explanation [1:07] makes it sound as if the trick is to simply pick a temperature above the BP of the lower liquid in solution - but my understanding is that when you have two liquids mixed, they will produce a solution with a BP that is somewhere between the two individual BPs, relative/proportional to the ratio of the mixture - that's Raoult's Law, right? And it is not linear, but has a negative or positive deviation from a line between the two BPs? So to distill a mixture, you need to heat the liquid to the BP of the *mixture* so that when the mixture boils you get vapours coming off that you can readily distill. If we don't heat the mixture to it's BP, only evaporation vapours will come off the liquid, which is not at a very fast rate, right? Something else you said I didn't understand [6:20] how can we heat the liquid mixture past it's BP? It isn't like in a liquid with two substances there is some of the stuff boiling off at one temperature and we can keep heating it to the next BP where the other substance starts coming off as gas, that violates Raoult's Law. At the BP of the mixture, all the energy is going into the latent heat of vapourisation to turn it into gas, yes? Like, you cannot heat water past 100C because the energy goes into converting water into steam. At a 50:50 mix of alcohol and water, that'd have a BP of a bit over 81degreesC? zenodo.org/record/1513542/files/article.pdf So it should not be possible to heat that mixture beyond ~81C, any excess energy will go into making gases. The temperature of the liquid will eventually rise, but only as the ratio of alcohol:water changes affecting the BP (so a 10:90 solution will be boiling at about 86C, yes?) [6:04] What we definitely want to do is control the rate of heating so we keep the boiling to a low rate to avoid violent boiling and an excessive vapour rate that exceeds the ability of the condenser to knock down the vapours into liquid. We want enough energy going into the liquid to keep the liquid boiling gently and pushing out those gases, but we are controlling the amount of energy being put into the process of vapourisation to keep control of the rate of the process - not preventing the temperature of the liquid from rising past the BP - yes? Also [1:15], my understanding is that the vapour coming off the liquid mixture is not purely composed of the substance with the lower BP, but is itself a mix of the two solutions, but in different proportions to the original mixture, with the vapour ratio having a higher component of the more volatile substance than the ratio in the liquid. chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Equilibria/Physical_Equilibria/Raoults_Law_and_Ideal_Mixtures_of_Liquids The result is a liquid with a reducing mix ratio, but not purely 'leaving behind' the liquid with the higher BP, right? I think this is what you note at [7:31]. For data collection, [7:08] another possibility that would have been interesting would have been to periodically sample the distillate, measuring the proportion of water and alcohol in the distillate using a refractometer - it would have shown the earliest distillate samples had a higher proportion of alcohol than later samples, due to the reducing alcohol-water ratio in the flask. And [1:20] because the vapours coming off the boiling liquid are a mixture of the substances, just in a different ratio than in the original liquid, when the vapours are collected and cooled, the distillate is not pure but just purer than the original liquid mixture - yes? So to work toward purity, the distillate needs to be re-distilled, because the distillate will boil off vapours that have a higher ratio of the more volatile substance...? So at [8:25] the distillate cannot really be said to be isopropyl alcohol separated from the mixture, we can really only say that it is purer than the initial mixture - right? The clarity of the distillate - could this be due to the low volatility of the dye, meaning the proportions of the dye in the vapour mix is negligible? It surely cannot be used as a reliable indicator of the proportion of the water to alcohol mix in the distillate...? I understand that it is sometimes necessary to make simplifications to explain concepts, but I do think that the way I was taught chemistry at school (including this idea of the lower BP substance boiling off first) means I misunderstood things that I had to unlearn later. I don't think it is too hard to understand the idea that a mixture takes on a BP somewhere between the BP of the components. Also, I don't think it hurts for us to learn early on that processes like distillation are not 'perfect', we don't get 'pure' anything out the other end, that is a useful thing to know. And WHY that is the case might be something that is left for a more advanced class, but at least we aren't left with misunderstandings from oversimplifications? I mean, it isn't necessary to over-complicate things with explanations of azeotropes and why this means you cannot actually distill 100% pure alcohol from an alcohol-water solution, simple is good, but too simple isn't great, surely? Oh, - and a big thank you for the free public education work you do.
I have found this physical chemistry lesson by Steven Stuart to be very informative: ua-cam.com/video/ZV6J3UgV31I/v-deo.html but it would be great to have a video like yours that explains this behaviour in a simpler fashion for the sort of audience you were aiming at.
You have a good understanding of the situation, but distillation CAN achieve complete separation of volatile compounds. If the b.p. difference is high enough and there are no azeotropes, essentially one liquid boils first then the other. If the difference is small, you still can achieve separation with a fractionating column or, using better technology, with a spinning band distillation apparatus. This happens because you have thousands of theoretical plates: it is like redistilling a thousand times in one shot. I have separated liquids which differed in b.p. by 1-2 degrees, each >99% pure. Bottom line: this video refers to the practice of distillation, and I do not think it wanted to touch on theory, which is extremely complex. There may be other videos explaining that.
@@galileog8945 if the substances have a negative deviation from Raoult's Law, then yes, purity is possible. Those are rare mixtures though. For all positive deviations from Raoult's Law, even those without azeotropes, many theoretical plates achieves an approximation of purity (like >99%) not actual purity.
@@JeremyTaylorNZ When you separate substances by distillation, I do not think you need to know if there are deviations from Raoult's law. Complete separation is possible, and the more theoretical plates you have, the more complete it is. Practically speaking, 99% is pretty good, but it is not a limit. "Approximation of purity" has no meaning in chemistry.
@@galileog8945 I should have said 'strong deviations such that there is an azeotrope' not just 'deviations but it is in fact important and relevant to whether you can produce what anyone would call a pure substance. For instance, because ETOH and water have a min-boiling azeotrope, it is impossible for a distillate with even a billion theoretical plates to get beyond 95.6% alcohol by weight - which is a long way from 'purity', where a chemist has the capability of measuring contamination down to ppm ua-cam.com/video/VO5P7PT8gI8/v-deo.html
I could have taught color wheel and absorption transmission spectra better!
How can I convert mercuric 0xide too liguid Mercury
Hi my name is John Castor I want to find out if there was any way that I could get some help with help with getting some lab glassware because I am very short on that I'm trying to start off a small business of extracting lemonade and extracting the pepper extracting different extracts of different species of plants thank you very much I would very much appreciate that thank you
Hello, I think I can help you
You say simple but Scotland makes a mint out of this from barley
I would like to separate sperm from seminal fluid. What temperature should I use?
Same as you usually do. The temperature of your mouth seems to work just fine so why change the process now?
Time to be the richest high schooler in existance
Hey, I dont know if this is where I would say this but this might be a good debunk type video topic. There is a company called Solex LLC that sells these sham "frequency" type products. Typical quantum mysticism word salad, they can apparently "scan your body" and "balance your frequencies", just a whole lot of tripe. However, their products are geared toward people with serious diseases, and claim to be able to effortlessly cure anything from cerebral palsy to cancer. (This includes a close family friend of mine, who our mom bought some of their products for.) They also charge absurd prices for things that are incredibly easy and cheap to produce, going so far as selling unmodified tablets that you can buy for a few hundred dollars, for over a thousand dollars. This is a horrible company that is personally hurting people I care about, so if this seems like a good topic to tear apart, that would be amazing. Thanks!
Need Nitroethane , can i get?
Look, if you want to make moonshine, just make moonshine :D
Great info! Thanks!
What is the point of this experiment?
It’s explained quite clearly in the video.
@@ProfessorDaveExplains Not being argumentative and this video is good. But, what can be achieved by this experiment?
My apologies. I'm just not in the know.
Only curious
Thanks
Separation of the components of a mixture by virtue of difference in boiling point. Again, it can’t have been explained more clearly.
A-train doing chemistry classes lol
Thank you physics jesus
🤣 IM DEAD
organic chemistry 101
كم سعره؟
i love this😀😀😀😀😇😇
yeahh!
thank walter whute 2.0
I have a business opportunity for a man of your skills
Cool
Not available in our house. Not simple.....
Collecting distillate in a graduated cylinder? Sure, why not...
Why not? I've done it
@@markshort9098 Yea, there isn't any reason not to. I just hadn't ever done it before for whatever reason.
@@alistairmaleficent8776 i like doing it for certain things just because it gives instant feedback on how much has been collected
shrimple
t h a n k y o u ! awesome video!
👍👏
i come after years and i hate to see it , NOOO HAIRSSS 😭😭😭
Im cooked tomorrow 💀
Did someone say Toonshine?
👏👏👏👏👏👏👍⚗️
😢😢😢
Ooo
uwu😖
You don't do content about atheiism anymore
I never have.
It’s a dead horse, honestly
Balding Reddit mod 🤣
?
Indian😅😅😅😅
Hi Dave. What is your PhD in? my guess is chemistry. Just curious as another nerdy scientist.
From what I recall, he has a bachelors in organic chem and a masters in science education.
he does not have a phd
Then how did he aquire that professorship degree @@PakkiNakki
moist critical
Nuh-uh! A round-bottom flask? It is obviously a flat-bottom flask, open your eyes! When you take into consideration the refraction of the light within the container it is obvious that the surface is flat.
Nice try NASA shill but the coriolis effect is not possible on your model. The curvature is simply artificial because of the fish eye effect of our eyes.
Here is 100% proof that it is not a round bottom flask, but a flat bottom flask:
If you were to cut it in half, why does it look like a *dome* ???? OPEN YOUR EYES
Diffraction. Reverse refraction. Angular perspective.
rising eye level. Def leppard. diminishing visibility level.
I wet my pants last night.
All proof against your "science"
@Walter Holding a Banana what gave me away, the Def Leppard part?