Basics of chromatography | Chemical processes | MCAT | Khan Academy
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- Опубликовано: 16 сен 2013
- Understand the basic principles of different kinds of chromatography: paper, thin layer, column, size-exchange, ion exchange, affinity, HPLC, and. By Angela Guerrero. . Created by Angela Guerrero.
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Hi..the video is great..but you have made a mistake with size exclusion chromatography..the molecules that are larger in size (the ones excluded from the beads due to larger size) are the first ones to elute out followed by the small, the smaller and the smallest..the reason being that the molecules which can enter the beads via the pores have a longer path and hence a longer transit time.
upvote so others see
That is a different concept in general. So im not entirely sure this applies. Correct me if im wrong, but in liquid chromatography size is a factor yes, but polarity is the main concern here.
Correct
Shout out to you! Thank-you for your simple yet complex explanations because I completely understand this topic now and feel confident to write my extended response!
The point on size chromatography is wrong. Larger size elutes faster as it can go around the beads, whilst smaller beads have greater retention as it has to go through the intriciate pores.
True that.
@@hargobindsingh3167 oh is it? Cause even we studied about the larger ones eluting fast.
@@peepdi sorry was wrong here mixed a concept😅
@@hargobindsingh3167 it's completely fine 😁
This is indeed true. Smaller molecules travel through the porous beads thereby making their path to elute much larger than that of larger molecules. I am an advance biochemistry student lol
* correction, it should say: in size- exchange chromatography, small particles get trapped in the column by the small beads, thus small particles are slower to move. I just read that in Kaplan MCAT biochem review.
That was extremely helpful, thanks!
6:28 In size exchange(exclusion) chromatography, aren't they the bigger molecules that move quicker than the smaller ones because the smaller ones have to travel in the beads?
+Gemechu Bekele Yes.
Yup agree. In size exchange chromatography if the size is too big it wont pass through the beads instead it will flow through the column. Only small particles will flow through the beads hence, smaller particles is said to have higher retention time
emeg losota yes
It's the same principle as DNA Gel electrophoresis, there's no limit to the length of DNA that can pass through the gel. Really long molecules will travel with smaller ones through the silicone, but much slower.
@@VincentStevenson no not same principle, larger DNA pieces travel less further due to interactions with agarose gel. whereas in SEC larger elute out first/travel faster as they do not get stuck in the holes of the bead
That moment when a 4th grader becomes your teacher :P...
+Gemechu Bekele
The moment you fail verbal reasoning because you can't take a joke
+Gemechu Bekele how do you know it is not a fake channel?
+Gemeche Bekele, that joke not only flew over you, it fucking soared past at fucking mach 6 lol
I did not type that it was my friend for reals
it was my friend
Thank you soooooo much. This will definitely help me with my lab
Thank you, very informative!
I had no idea what it meant, but then I realised I did this at primary! Thanks
Soo beautiful voice
And you explan clearly
Thanx for sharing knowledge.... 🙂
Thank you so much ! Have exams soon and this assisted me :)
thank you so much those extremely helpful!
extremely helpful :) love your voice :)
Thanks for the helpful video..I've made a simple at-home experiment involving paper chromatography but instead of drawing a dot..I drew a line with a black pen used for whiteboard..and it separated to 3 colors as I remember..and I used a mixture of water/ethanol to get the best separation!
You totally sound like Alphonse Elric from Full Metal Alchemist: Brotherhood. Amazing video, by the way. Thank you.
You're absolutely right, I can't unhear it now :/
Absolutely.
Oh my God yes she does!
When your a weeb and u spent all the time watching anime and now is studying 1 hour before the exam
this video made it make so much sense THANK YOU
thank you. this was very helpful.
Great video, super helpful thanks
u just saved my life thank you so much
me to thanks got a test common up and this helped me :)
Thanks, very helpful.
this was helpful. thank you!
thanks helped alot!
Beautifully Explained!
Nice video really helped before exam thanks you so much
Than you very much for the help. the way you explained paper chromatography made it extremely simple. Again, thank you for such a video
Thank you so much for making the video. If possible, could you please change the font color in the future? As It is quite difficult to read your note toward the end of the video. Thank you again for your time
khan academy is my favorite channel. by the inspiration of this channel i started my channel covering all topics regarding pharmaceutical analysis & biochemistry. i did video on basics on chromatography.
Aww, her voice is so cute
Thanks girl ! The best here 👏👏👏👏👏👍👍👍👍👍😙
this video help me so much... tq :)
very nice...
thanks a lot for the video.
..
Great video.. more information in least time..✨✨✨
Love your pictures. They are GREAT: )
Should probably mention most often for HPLC the silica gel is bound to a nonpolar group, so the more polar group elutes first v. all other techniques the more nonpolar group elutes first.
Doesn't that depend on the solvent that is used? In most cases, it would be polar solvent, hence the most polar compound would elute first.
excellently explained !
Thank You very much
Thank you.
yes you are right and like
thank you for the great content.
This helped for science olympaid thanks!!
Wait! Were you doing crime busters?
Thank you so much
I think that you have it backwards in Size Exclusion Chromatography. The larger molecules can travel faster because they are not distracted by the other paths that can be taken to reach the end of the column.
+Joseph Landavaso No, she's right - the larger molecules travel slower
+Chris Koperniak in size exclusion chromatography the large molecules elute quicker. The small ones get stuck in the beads. She is wrong.
This video is awesome ❤️🔥❤️🔥❤️🔥, I understood completely
Helping me out for my regents today ☹️✅
Thanks a lot 🙏
Thank you !! Extremely helpful
our comments look pretty young out here 🤣.once upon a time Khan Academy used to be a very popular educational channel
her voice is so soothing
In paper chromatography, the stationary phase is not the paper but water adsorbed into the paper
Very very helpful ❤️
Interesting. Seem to be a few accuracy issues though. But it's a good video
The stationary phase is actually water trapped between the cellulose fibres of the paper.
Thanks this video helped me a lot!
kewl
Most underrated channel
4:32
COMMENTATORS SHOUTING : W...W...E.... Tables Ladders and Chairs
TLC.
I love it 😍
That sounds like evalion. Would be pretty cool if she is doing chemistry now.
everyone is either 1) sexualizing the speaker 2) criticizing and comparing the speaker to Sal... what does that even say about you guys? Lovely video, they're just jealous you understand chromatography and they don't.
you should choose a better pallette of colours, some couldnt read what you wrote in the hplc, like me.
x1.5
+MrElectricSkittles Expert call right here
thx
Hi yall
ye i really got annoyed and changed the playback speed
Thank youu
In paper chromatography, the stationary phase is not paper but the liquid that is bonded upon it.
Fantastic ❤
Can u plz make a tutorial on ascending paper chromatographyy
Very good and simple explanation,thanks :))
kindly add true expt. which would be easy to understand
Bro this video helped a lot with my science assingment in Year 7!
same
@@Philippine_Navyist16 I got a B+ for this video! I could've gotten an A if I hadn't gone over time!
@@TheChessRobloxian todya is teachers day and no school, i dont know if my science teacher will approve this tom. Wisj me luk
@@Philippine_Navyist16 wdym ur science teacher won't approve? anyways good luck.
@@TheChessRobloxian yay he aprovves
10/10 ign
most intrtuiging thing ever
What happened to Sal's voice? 0_o
It's a KA spin-off
+ChimChim I just scroll the page to see some of the comments idk why and I saw your current profile pic... BTS is following me even in my hw ;o;~
Ikr?
He started listening to Jo Jo Siwa and then his voice changed. It's sad. Don't listen to Jo Jo Siwa, kids.
I m in love with your voice😀😀😆
And yes this was very useful thanks!!!
so, the capillary action will take place in both?
You are explaining GC as if it is fractional distillation.
Good drawings, but needs to concentrate and remember the speech
Stationary Phase in case of paper chromatography is liquid, because it has molecules of Water.
Does anyone have some videos I can use for science Olympiad
nice work keep it up
Brief, precise, nice and short, although there is an error in size CrGphy. Excellent job 👍
very good
very nice
is lipid molecule separated with the help of gas exchange chromatography?????????????
wow thanks pushed my grade from an f to an A*. I'm gonna now major in chemical engineering to make the fortnite chug jug real
so which substance is more polar? The one closer to the stationary or mobile phase?
Theodore Goujon. depends on the the type of stationary phase/mobile phase you use.
Thx ima make ricen now
Came here from the video too
danke
Hi fbi personnel I'm not makeing ricen I would die doing it and I have no uses for it
where is this on the website?
5/5, would watch again
Aren't the water molecules trapped WITHIN the cellulose fibres of the paper the stationary phase and NOT the paper itself?
+Mamma Harun yh but it better to say the paper as the cellulose is needed to keep the water stationary
There are two principles on chromatography~
1) Adsorption
2) 2 phases (Stationary and moving)
Am I right?
Ishu
1) adsorption
2) partition
Akarui Orenji Oh yeah thanks :3
Ishu
Cool
Nice
What is cpillary action
good
beautiful voice.
are fucking kidding me she sound slike a 7 year old boy with a clogged nose. You must be some fucking omega-virgin.
and this is why i love reading comments
Nice Student idk why but "some kind of fucking omega-virgin" made my day
ikr
ty m8 I really felt it while typing
Munna sir's advice.
is her nose blocked or something? but good video
Can someone please explain how paper chromatography relates to spotting fake paintings? If the colors travel farther then does it mean that the painting's fake or the other way around?
Old paintings used colours that were different in composition to those that are used now because alot of old paints were carcinogenic and toxic, they perform the chromotography stahe and the dissolved paint will elute at a certain time which is recorded. This is known as the retention time, and can be considered a fingerprint of the molecule as it is unique for every compound. This retention time is then compared to a database of compounds with known retention times and will display compounds that correspond, they then can check the manufacture date of the compound to assess the age of the painting and therefore distinguish whether the painting is real or fake :)
Cute voice.
should choose a better pallette of colours, i couldnt read what you wrote in the hplc
Nick Hon are you colourblind?
Cute voice