Lec 10 | MIT 5.301 Chemistry Laboratory Techniques, IAP 2004

[hairytoothgaming]

Great video! Thanks for sharing.

[ChemistDrummer]

You forgot to add another "Caution!". Never clamp the pressure tube in place when having the stopcock close like shown in the vid. Danger of explosioni if you dont release the pressure quickly enough.

[cyclestring]

great vid. . I learned a lot about column chromatography. . thanks pal! :)

[Bakugantsuvai1]

The way she shows us the video is so funny

[dianafeiteira]

fml i dont undrestand nothing about this...im so screwed :(

[bassmanjr14]

use heptane, better for the environment

[lexichronicle2]

"There are also columns available with sintered discs at the base to avoid the cotton and sand part"

Speaking of which, I was just watching a column video that involved such a sinter, and the top of the column was bent, whereas this one is flat. indicating that care can overcome better equipment.

[Silverweed]

Having to collect 100+ fractions and spot all of them on TLC only to realize you didn't get enough separation. Having the column fissure right after adding your precious sample and having to recover every bit you can rotovapping down tons and tons of solvent praying you can get everything back. ughhhh never again please!! :P

[commercialmats]

This is really interesting. Thanks for this vid

[mlopes87]

nice beakers

[534Anthony]

why is a layer of sand used on top of the cotton?

[s1mon1337]

@534Anthony To make sure the silica gel is flat on both sides (the bottom of the column isn't flat if you don't add sand over the cotton)

[leboliciousMOZIE]

great video, really helped, excellent intro for new ppl

thank you.

[Pavel86]

Nice video!

But I still hate running columns

[HelloBrainMind]

STILL don't understand this.

So if you have a solution of two compounds that are closely related in polarity this makes sense, but how do you scale this up? ?!?

Ughhhh.

[Silverweed]

@HelloBrainMind An automated system like biotage.

I wish I had this video when I was an undergraduate. Its every bit of knowledge I eventually sucked up while running tons of horrible columns separating cis trans isomers that would barely separate and took forever. One thing that I didnt notice, she may have mentioned, is that dissolving silica in polar solvent is exothermic and can heat the silica enough to make fissures and ruin the column. Watch out!

Great video!

[406356690]

whats the music in the beginning of the video?? anyone know plz tell me, been looking it for years..

[steeeee33z]

debussy arabesque no.1

[406356690]

@steeeee33z thank you!!!

[ilavm0]

realy nice work

[gshivashimpi77]

In this video it is been told that, to make slurry of silica gel, use the chosen solvent mixture. That is totally wrong. Actually one should use least polar solvent among solvent mixture (Like Hexane in Hexane/EtOAc system and Chloroform in Chloroform/Methanol system etc). Other things are perfectly explained.

[ChemistDrummer]

@gshivashimpi77 you are wrong my friend.

hexane,EtOAc or a mixture of them and likewise chloroform and methanol are the most common solvent systems used but it all depends on the mixture you want to separate...

[svenp]

This is wonderful.

[tie1978]

your hands work faster than your words...in my country they do it vice versa...thanks God we still have a good lecturer like you...

[RatkoUSA]

Great refresher video... Thanks a million, MIT

Now, with a little luck there's a lecture here somewhere on GLPC

[riclop]

Excellent!! this video helped me a lot!

[diegeilstesauderwelt]

great job! boys of erlangen!

[elssokkary]

thanks for this excellent movie

best washis

Kareem elssokkary

[timhortans]

I have to do a flash chromo in like 23 hrs did not know anything before watching this. thanks alot.

[atifzmn]

It was experimental if you illustrate theory as well,it would be really helpful for analytical students.

[lovelymanforu2004]

it was part of a chem lab course, for theory you go to the normal chem course on mit open course

[mrpopeye17]

Great video... I have an exam on columns this afternoon and this really cleared some things up!