THIS HELPED ME SO MUCH WITH UNDERSTANDING.. you’re literally getting me through school at this point. Thank you
@angelicapilar193 жыл бұрын
Prof. Dave always the best! I wouldn’t be able to write lab reports if it wasn’t for you
@aphrodite90425 жыл бұрын
I love you professor Dave , you have no idea how much you've helped me
@flowerblossom41314 жыл бұрын
Agree
@louisdelellis4638 Жыл бұрын
First time I've actually understood Column Chromatography. Thanks a ton!
@Lumax965 жыл бұрын
Really diggin the new haircut dude!
@bernarddoherty40143 жыл бұрын
Jesus H Christ! More complicated than a mission to Mars!!!😂😂
@inexp16 ай бұрын
what
@nurdagstanl95302 жыл бұрын
This video is literally beneficial to perceive how this process go.
@serenemoussaoui66135 жыл бұрын
This is an amazing explanation! Please keep it up!
@kevinnguyen11334 жыл бұрын
I had to double check if it was the right channel haha... nice look!
@marknluke35315 жыл бұрын
The new haircut suits you
@wafeeqahqazi5 жыл бұрын
True
@phuongphan7945 жыл бұрын
absolutely trueeeeeeee
@dgs3275 ай бұрын
Focus on studying, bro
@mckenziekanna22063 жыл бұрын
professor dave is an icon among stem students
@emteemte3985 Жыл бұрын
What a sweet profesor you are. Thank you very much. You made me chemist
@DonaldDuligi3 ай бұрын
Watching from Papua New Guinea 🇵🇬. Thanks, Professor Dave. It was really helpful.
@RafalSB4 жыл бұрын
so helpful. I've watched it a few times already. Thanks!
@aphrodite90425 жыл бұрын
Loving your intro 0:03
@MrDarth443 жыл бұрын
Okay. its official. i love you dave. you made my Lab report so easy and understandable.
@Artavazd.kirakosyan3 ай бұрын
Thanks for the explanation, what sand are being used at the top? what is its function? any alternatives of sand? or can it be omitted?
@onelenkangezi69882 жыл бұрын
Having to do this practical tomorrow. it will now be absolutely easy to do it
@no_shit5756 Жыл бұрын
"make sure to do this in a hood to avoid inhaling" 💀. I cook some other compound in the hood specifically to inhale it.
@rluisnha Жыл бұрын
Great Professor Dave. after watching your videos I feel able to run column chromatography to separate compounds
@danielchandi81987 ай бұрын
i always come back to videos of professor Dave, such great videos
@sultan.s3iii6015 жыл бұрын
why we should dissolve the mixture in the smallest amount of solvent? Like what happens if we add more - Thanks
@ProfessorDaveExplains5 жыл бұрын
good question! so we need the sample very concentrated in a thin band so that it can separate in a distinct way. if it is dilute, then all the molecules would have different starting places as they load on to the column and you'll get very wide bands and insufficient separation.
@cziasicat44882 жыл бұрын
Thanks. You deserve a like and good comments for your videos.
@fatemahussein29203 жыл бұрын
Thanks a lot. Please could you make a video about symmetry and group theory
@akiharu19995 ай бұрын
Is it okay to use any type of sand? Or is it okay not to use sand at all? Thank you!
@wandererrrrrr6 ай бұрын
Fourth year of pharmacy school and still benefit from you
@hidayahreshidan17263 жыл бұрын
Hi Prof. I enjoy watching ur education video. I am Hidayah from Malaysia.
@Dr.SahithyaSelvaraj20 Жыл бұрын
Thank you so much Prof. Dave... You saved me!!!!
@emteemte3985 Жыл бұрын
I love now tlc and column chromatography because of you love you
@SimonPeapo Жыл бұрын
Thank you so much Professor Dave for such an amazing exploration ❤ ❤😊
@muzeyyenbuyuksamanc6885 Жыл бұрын
Thanx for the video, I've a question the compound that we obtained first , blue one 07:55 , is more non-polar, isn't it?
@hubertseidl935 жыл бұрын
Well, if I would have it done that way, they would have fired me. First, buy a real column, not just a fat pipe. That helps keeping the gel clean (you don't want to have sand interfering with you product, or even mixing with the gel, when you unpack your column). Second, packing your column: at the bottom should be some sort of fabric that doesn't allow the gel to go through. mix your gel with a saline or polar solution to generate the slurry. usually the gel manufacturer will tell you how to pack the column. Fill in your gel, then add the upper stamp (with fabric), make sure there are no air bubbles, and start pressing with a constant flow rate (from a pump) to pack the column. Third: lower the stamp to the border where the gel has settled, still in constant flow. Congratulations, the column is packed. Forth: Check the packing of your column by letting a small amout of UV-absorbing molecules through the column. You neither want to have fronting or tailing (different shapes of the peak), nor a broad peak that indicates that your column is doing a poor job at seperating. fifth: Do the chromatography with a constant flow, some pressure and maybe even a pressure restrictor at the end of the column. And you need some sort of identification of your product, or at least a way to measure that you get different products. UV-light is very helpful, pH and conductivity are helpful aswell. you also mentioned, that the Gel should not run dry: good advice, it usually lowers the quality of your packing. Some gels can be recovered by reverse flow, push the air out of the column. others, especially size exclusion gels are essentially done. go back and repack the column. and there are some gels that will not tolerate air at all, meaning, that you have to throw it away, etc. A friend of mine once told me, that he had a gel worth 2 million € in his column (I don't know what it was made of, but it was experimental), and he was very cautious not to make any mistakes, because that stuff was super expensive and if it happened to be destroyed, the manufacturer of that stuff actually needed to set up a new batch in production.
@alishamunwar7294 Жыл бұрын
Sir I HV a question pls I will do this technique and I wanna ask how much would be the size of cotton swab use and for column which type of burrete is suitable???
@philipcrisp7278 ай бұрын
Can you do a video on GC or HPLC please?
@alishamunwar7294 Жыл бұрын
Sir let me know that can we use tolune and ethanol in column .. pls tell how much sand is good in grams etc..
@Ambient_Scenes3 жыл бұрын
Sorry to keep asking you questions Dave. I'm really hoping to understand this though. Assuming you happen to have a gas chromatogram or HPLC chromatogram of your sample (in some solvent), can you somehow use the information in those chromatograms to bypass the thin layer chromatography step? And would you then use the same solvent you used for the gas chromatography for the column chromatography?
@WetDoggo Жыл бұрын
I don't find it complicated at all, but it's definitely a really clever way to the separation problem. I like it ❤
@137bob3d4 жыл бұрын
a very well done intro presentation. if you would , please ... a few questions ... the matter of mesh size of silica gel in the column ... for a gravity driven elution is the mesh of the TLC strip too fine to copy ? by 'too' fine' i mean would the flow be so slow to not finish in a lab session ? ... and the fractions ... given the stopcock ... is it ok to stop the flow after each one and spot it on a 254-tlc plate... let it dry ... then shine uV on it to see if anything is there ? and if nothing shows up could this volume of eluent be poured back onto the column top ? i'm hopeful to find follow up vid's on this topic. to learn , for instance, how one chooses mesh size of silica and the gradient solvents , plus column size and the amount of silica vs. sample size.
@parinazmika2 жыл бұрын
you are the best teacher eeeeevvvvveeerrrrrrrrrrrrrrr❤❤
@alishamunwar7294 Жыл бұрын
Sir pls tell on top sand which solvent should be added by pippte is it the solvent in which our sample is soluble????
@tekalignthomas85244 жыл бұрын
wow amazing explanation bro thanks
@anishgupta28645 жыл бұрын
Looks great in that hair style
@fakhrulnawawi96813 жыл бұрын
What's solvent use to dissolve sample? Can I use the mobile phase, hexane Ethyl acetate?
@saiii.425 жыл бұрын
Helps so much thank you!!!!!
@yvvkranthikiran3 ай бұрын
Thank you
@matchmedicines82094 жыл бұрын
thanks a lot, the same as always very nice with all of the details.
@nabilanuragusti31453 жыл бұрын
Thank you very much, Prof..
@diyagupta89903 жыл бұрын
your videos are so helpful! Thank you for these!
@Kissoveryou5 жыл бұрын
i'm learned from video . tks you
@elpidakeremidou37023 жыл бұрын
Thank you very much for the explanation!!!
@user-hw7fq9uo3m10 ай бұрын
Thanks
@shariqsultan58113 жыл бұрын
Professor..I work for chemical reasearch industry...my question is I m working on my project which is I have to seperate two isomers spots in TLC are very close, now the problem is if I pack a coloumn of 250 gram (crude) after completion of columns I only get 100 gram pure,most of the fraction shows dual spot...that's why my yield is decreased that's why please resolve my problem,, reply me sir please
@El-wv1tf Жыл бұрын
hopefully you have resolved the problem, since it was a year since the question :) I would tweak mobile phase to get those zones further away from each other
@pharmasolutionpakistan76682 жыл бұрын
I appreciate u. M also a lab trainer
@fakhrulnawawi96813 жыл бұрын
Very clear.. Thank Prof
@kagamer212 жыл бұрын
Thank you professor!
@santhianpalagan96165 жыл бұрын
Bro why we are adding the upper layer of sand to fill the holes of silica gel or to fulfill the coloumn
@ProfessorDaveExplains5 жыл бұрын
it's just nice to have something to separate the stationary phase from the mobile phase, but to be honest i've run columns without the top layer of sand
@santhianpalagan96165 жыл бұрын
@@ProfessorDaveExplains thankyou sir nicely explained
@santhianpalagan96165 жыл бұрын
@@ProfessorDaveExplains sir im sorry to ask that again is there any holes in the silica gel. Òŕ we are adding the sand just to fill the coloumn what is the actual usage of the sand And im 15 years sir so i dont know more scientific terms because im tamil please explain me simply
@ProfessorDaveExplains5 жыл бұрын
no, the gel must be packed well, no holes or cracks.
@santhianpalagan96165 жыл бұрын
@@ProfessorDaveExplains so the top layer of sand is to fill the coloumn
@s.g.n.msirisena42614 жыл бұрын
Thanks for lot that was more helpful to me
@ruhidyusifov51062 жыл бұрын
Thank you so much you are the best!
@worldwidechemistry.86512 жыл бұрын
Thank you prof.
@kavyakl51085 жыл бұрын
Very nicely explained... 👌
@137bob3d5 жыл бұрын
great presentation. you enunciate so emphatically and clearly, good going. this vid's been added to my favorites one thing i'll remember is that the loaded sample has to be within the silica phase. and not any above its top edge ... in the above sand layer. on the topic of the sample transparent and the desired product being clear too. does it happen that chemists add color dyes with an Rf that brackets the produce as an aid in locating it when it exits the column ? lastly is it ok to close the column for 10 minutes to TLC the fraction ? or does the eluent flow have to be non-stop ?
@earthworm-filledstomachbyc42544 жыл бұрын
Professor Dave: what degree do u have in undergrad?
@ProfessorDaveExplains4 жыл бұрын
chemistry
@arminarlert173 жыл бұрын
Thank you so much!
@rassimsimou15942 жыл бұрын
Good
@Abhi-ph4ks2 жыл бұрын
Thank you.
@haha-rx5xn2 жыл бұрын
Thanks you sir!!
@jarodduesing17282 жыл бұрын
Thanks!
@mscyl20003 жыл бұрын
Woah professor Dave.
@pharmasolutionpakistan76682 жыл бұрын
Good job
@rapunzel_77993 жыл бұрын
What's the purpose of sand?
@doomedfleur12974 Жыл бұрын
The eluent is opposite to the stationary phase?
@ProfessorDaveExplains Жыл бұрын
Travels through it.
@noirsyad4617 Жыл бұрын
love u prof
@watching441010 ай бұрын
How is this different from gas chromatography
@alphagonist47483 жыл бұрын
Thanks sir
@fyrerayne88822 жыл бұрын
nice, thank you
@BilalSk36565 жыл бұрын
Wao. Amazing
@HapinessAyo3 ай бұрын
Why does column chromatography seems so hard to me 😢
@PakChemist2 жыл бұрын
You look great
@VikramSriKrishna3 жыл бұрын
How much silica we have to load???
@CutecatGoldi3 ай бұрын
10 times the weight of mixture
@bigermac1235 жыл бұрын
My first column is tomorrow.. Wooo
@BilalSk36565 жыл бұрын
New hair style...waoooo
@akimhaq16164 жыл бұрын
👍🏻
@rpb5375 жыл бұрын
haircut took 6 years off your age
@Nexus2Eden5 жыл бұрын
Just wanted to say - Love the new do! Sexy man there...😉👍