Basics of chromatography | Chemical processes | MCAT | Khan Academy

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  • เผยแพร่เมื่อ 24 พ.ย. 2024
  • 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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ความคิดเห็น • 279

  • @metoo2here
    @metoo2here 11 ปีที่แล้ว +400

    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.

    • @5Youssif
      @5Youssif 7 ปีที่แล้ว

      upvote so others see

    • @iansteinke2414
      @iansteinke2414 7 ปีที่แล้ว +5

      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.

    • @EDERDUDE
      @EDERDUDE 3 ปีที่แล้ว

      Correct

  • @trilliumchang4127
    @trilliumchang4127 8 ปีที่แล้ว +411

    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.

    • @peepdi
      @peepdi 5 ปีที่แล้ว +2

      True that.

    • @peepdi
      @peepdi 5 ปีที่แล้ว +2

      @@hargobindsingh3167 oh is it? Cause even we studied about the larger ones eluting fast.

    • @hargobindsingh3167
      @hargobindsingh3167 5 ปีที่แล้ว +3

      @@peepdi sorry was wrong here mixed a concept😅

    • @peepdi
      @peepdi 5 ปีที่แล้ว

      @@hargobindsingh3167 it's completely fine 😁

    • @robertsanchez4316
      @robertsanchez4316 5 ปีที่แล้ว +9

      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

  • @CORPSE77
    @CORPSE77 6 ปีที่แล้ว +24

    * 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.

  • @gemechubekele2546
    @gemechubekele2546 8 ปีที่แล้ว +99

    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?

    • @easylearning981
      @easylearning981 8 ปีที่แล้ว

      +Gemechu Bekele Yes.

    • @khadijahadam4387
      @khadijahadam4387 8 ปีที่แล้ว +5

      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

    • @learntosayno78
      @learntosayno78 7 ปีที่แล้ว

      emeg losota yes

    • @VincentStevenson
      @VincentStevenson 7 ปีที่แล้ว +1

      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.

    • @ND-ji8dk
      @ND-ji8dk 2 ปีที่แล้ว +1

      @@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

  • @kristak.1625
    @kristak.1625 5 ปีที่แล้ว +2

    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.

  • @EHBRod13
    @EHBRod13 10 ปีที่แล้ว +83

    You totally sound like Alphonse Elric from Full Metal Alchemist: Brotherhood. Amazing video, by the way. Thank you.

    • @A_Dopamine_Molecule
      @A_Dopamine_Molecule 6 ปีที่แล้ว +3

      You're absolutely right, I can't unhear it now :/

    • @firephoenix8192
      @firephoenix8192 6 ปีที่แล้ว +2

      Absolutely.

    • @kasondemulenga3472
      @kasondemulenga3472 6 ปีที่แล้ว +2

      Oh my God yes she does!

    • @ekhs2669
      @ekhs2669 4 ปีที่แล้ว +3

      When your a weeb and u spent all the time watching anime and now is studying 1 hour before the exam

  • @oliviadenyer-dobrowolski7441
    @oliviadenyer-dobrowolski7441 7 ปีที่แล้ว +8

    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!

  • @coreyking212
    @coreyking212 8 ปีที่แล้ว +359

    That moment when a 4th grader becomes your teacher :P...

    • @remusomega
      @remusomega 8 ปีที่แล้ว +55

      +Gemechu Bekele
      The moment you fail verbal reasoning because you can't take a joke

    • @sylvecakes8450
      @sylvecakes8450 8 ปีที่แล้ว +2

      +Gemechu Bekele how do you know it is not a fake channel?

    • @nathanbrown4689
      @nathanbrown4689 8 ปีที่แล้ว +24

      +Gemeche Bekele, that joke not only flew over you, it fucking soared past at fucking mach 6 lol

    • @sylvecakes8450
      @sylvecakes8450 8 ปีที่แล้ว +2

      I did not type that it was my friend for reals

    • @saintofchelseathomascarlyl5713
      @saintofchelseathomascarlyl5713 6 ปีที่แล้ว +3

      it was my friend

  • @bushraduti6780
    @bushraduti6780 10 ปีที่แล้ว +29

    extremely helpful :) love your voice :)

  • @AKASHVERMA-ok2ns
    @AKASHVERMA-ok2ns 6 ปีที่แล้ว +4

    Soo beautiful voice
    And you explan clearly
    Thanx for sharing knowledge.... 🙂

  • @albertchen2020
    @albertchen2020 5 ปีที่แล้ว +3

    Aww, her voice is so cute

  • @TheSurvivalSecrets
    @TheSurvivalSecrets 11 ปีที่แล้ว +11

    That was extremely helpful, thanks!

  • @georgefloyd5078
    @georgefloyd5078 ปีที่แล้ว

    her voice is so soothing

  • @vivaanmaheshwari9852
    @vivaanmaheshwari9852 ปีที่แล้ว +1

    yes you are right and like

  • @andreimaruis1860
    @andreimaruis1860 2 ปีที่แล้ว +1

    Thank you very much❤️❤️
    Now I know how to make ricin🫡

  • @jore354
    @jore354 9 ปีที่แล้ว +6

    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.

    • @chriskoperniak784
      @chriskoperniak784 9 ปีที่แล้ว

      +Joseph Landavaso No, she's right - the larger molecules travel slower

    • @naomik5213
      @naomik5213 9 ปีที่แล้ว

      +Chris Koperniak in size exclusion chromatography the large molecules elute quicker. The small ones get stuck in the beads. She is wrong.

  • @TheChessRobloxian
    @TheChessRobloxian ปีที่แล้ว +2

    Bro this video helped a lot with my science assingment in Year 7!

    • @Philippine_Navyist16
      @Philippine_Navyist16 ปีที่แล้ว +1

      same

    • @TheChessRobloxian
      @TheChessRobloxian ปีที่แล้ว

      @@Philippine_Navyist16 I got a B+ for this video! I could've gotten an A if I hadn't gone over time!

    • @Philippine_Navyist16
      @Philippine_Navyist16 ปีที่แล้ว

      @@TheChessRobloxian todya is teachers day and no school, i dont know if my science teacher will approve this tom. Wisj me luk

    • @TheChessRobloxian
      @TheChessRobloxian ปีที่แล้ว

      @@Philippine_Navyist16 wdym ur science teacher won't approve? anyways good luck.

    • @Philippine_Navyist16
      @Philippine_Navyist16 ปีที่แล้ว

      @@TheChessRobloxian yay he aprovves

  • @Chem4students
    @Chem4students 4 ปีที่แล้ว

    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.

  • @lauren9004
    @lauren9004 ปีที่แล้ว

    Interesting. Seem to be a few accuracy issues though. But it's a good video

  • @amanal-kabbani2745
    @amanal-kabbani2745 2 ปีที่แล้ว +3

    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!

  • @ashrafazman2859
    @ashrafazman2859 5 ปีที่แล้ว +1

    this video help me so much... tq :)

  • @suhanapandey2749
    @suhanapandey2749 3 ปีที่แล้ว +1

    In paper chromatography, the stationary phase is not the paper but water adsorbed into the paper

  • @hanan2184
    @hanan2184 2 ปีที่แล้ว

    this video made it make so much sense THANK YOU

  • @anousharahimzada5837
    @anousharahimzada5837 9 ปีที่แล้ว +2

    Thank you so much ! Have exams soon and this assisted me :)

  • @trilliumchang4127
    @trilliumchang4127 8 ปีที่แล้ว +12

    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.

    • @Nymeria0
      @Nymeria0 5 ปีที่แล้ว

      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.

  • @MrElectricSkittles
    @MrElectricSkittles 9 ปีที่แล้ว +102

    x1.5

  • @mekhicampbell3226
    @mekhicampbell3226 2 ปีที่แล้ว +1

    Thx ima make ricen now

    • @epic8924
      @epic8924 2 ปีที่แล้ว

      Came here from the video too

  • @nerdykityplantchild6301
    @nerdykityplantchild6301 10 ปีที่แล้ว +4

    This helped for science olympaid thanks!!

    • @legendarypanda424
      @legendarypanda424 4 ปีที่แล้ว

      Wait! Were you doing crime busters?

    • @wirekay
      @wirekay หลายเดือนก่อน

      You did science Olympiad, I’m doing science Olympiad rn

  • @sujanashwath9173
    @sujanashwath9173 11 หลายเดือนก่อน

    This video is awesome ❤️‍🔥❤️‍🔥❤️‍🔥, I understood completely

  • @iqtidarrahman2148
    @iqtidarrahman2148 9 ปีที่แล้ว +1

    I had no idea what it meant, but then I realised I did this at primary! Thanks

  • @aztec4194
    @aztec4194 7 ปีที่แล้ว

    Nice video really helped before exam thanks you so much

  • @floraacademics1195
    @floraacademics1195 7 ปีที่แล้ว

    kindly add true expt. which would be easy to understand

  • @sadamalinimalaweera4528
    @sadamalinimalaweera4528 3 ปีที่แล้ว +1

    Great video, super helpful thanks

  • @roheenamurad2375
    @roheenamurad2375 5 ปีที่แล้ว +1

    Stationary Phase in case of paper chromatography is liquid, because it has molecules of Water.

  • @DuyenLe-kf7gj
    @DuyenLe-kf7gj 4 ปีที่แล้ว

    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

  • @jasroop_sandhu
    @jasroop_sandhu 8 ปีที่แล้ว +10

    Beautifully Explained!

  • @Bhupender855
    @Bhupender855 7 ปีที่แล้ว

    Most underrated channel

  • @thilinaalagiyawanna3680
    @thilinaalagiyawanna3680 4 ปีที่แล้ว

    Thank You very much

  • @DuongNguyen-ni9gz
    @DuongNguyen-ni9gz ปีที่แล้ว

    excellently explained !

  • @mangatons
    @mangatons 8 ปีที่แล้ว

    you should choose a better pallette of colours, some couldnt read what you wrote in the hplc, like me.

  • @ruoyingzheng1680
    @ruoyingzheng1680 ปีที่แล้ว

    thank you for the great content.

  • @OMNI_INFINITY
    @OMNI_INFINITY ปีที่แล้ว

    That sounds like evalion. Would be pretty cool if she is doing chemistry now.

  • @NAGAVERSE
    @NAGAVERSE 5 ปีที่แล้ว +7

    4:32
    COMMENTATORS SHOUTING : W...W...E.... Tables Ladders and Chairs
    TLC.

  • @MrW0lfies
    @MrW0lfies 7 ปีที่แล้ว +1

    Thank you soooooo much. This will definitely help me with my lab

  • @jansenlimawan8415
    @jansenlimawan8415 6 ปีที่แล้ว

    Thanks, very helpful.

  • @KianDhawan
    @KianDhawan 6 หลายเดือนก่อน +1

    The size-exclusion chromatography is wrong. Larger molecules elute FASTER than smaller molecules due to the small molecules being trapped by the pores in the beads.

  • @imShifa
    @imShifa 5 ปีที่แล้ว

    Thank you.

  • @NK_2542_
    @NK_2542_ 2 ปีที่แล้ว

    Great video.. more information in least time..✨✨✨

  • @xxxyyyyzzzzzzz
    @xxxyyyyzzzzzzz 5 ปีที่แล้ว

    The stationary phase is actually water trapped between the cellulose fibres of the paper.

  • @ishu9176
    @ishu9176 8 ปีที่แล้ว +8

    There are two principles on chromatography~
    1) Adsorption
    2) 2 phases (Stationary and moving)
    Am I right?

  • @lalithkishore4249
    @lalithkishore4249 7 ปีที่แล้ว

    very nice...
    thanks a lot for the video.
    ..

  • @IIAmzazZ
    @IIAmzazZ 10 ปีที่แล้ว

    thanks helped alot!

  • @nancy8202
    @nancy8202 2 ปีที่แล้ว

    Very very helpful ❤️

  • @princessvirina1649
    @princessvirina1649 5 ปีที่แล้ว +2

    just to clarify things out, this is paper chromatography right????????

  • @57.zoonabatool61
    @57.zoonabatool61 3 ปีที่แล้ว

    Can u plz make a tutorial on ascending paper chromatographyy

  • @estrellasolimar9019
    @estrellasolimar9019 8 ปีที่แล้ว

    thank you. this was very helpful.

  • @kidsandkids5687
    @kidsandkids5687 2 ปีที่แล้ว

    Brief, precise, nice and short, although there is an error in size CrGphy. Excellent job 👍

  • @soham85e52
    @soham85e52 4 ปีที่แล้ว +2

    HELLO!

  • @tahsinrahman1668
    @tahsinrahman1668 8 ปีที่แล้ว

    so, the capillary action will take place in both?

  • @nonoooooooooo1
    @nonoooooooooo1 10 ปีที่แล้ว

    u just saved my life thank you so much

  • @hafsa1698
    @hafsa1698 9 ปีที่แล้ว +136

    What happened to Sal's voice? 0_o

    • @WaddiaS
      @WaddiaS 9 ปีที่แล้ว +8

      It's a KA spin-off

    • @lovelybias
      @lovelybias 8 ปีที่แล้ว +6

      +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;~

    • @nusaibahhussain9975
      @nusaibahhussain9975 7 ปีที่แล้ว

      Ikr?

    • @audreyandremington5265
      @audreyandremington5265 3 ปีที่แล้ว

      He started listening to Jo Jo Siwa and then his voice changed. It's sad. Don't listen to Jo Jo Siwa, kids.

  • @TheOnlyZackshadyK98
    @TheOnlyZackshadyK98 หลายเดือนก่อน

    Thank you v. much:))

  • @safeyyasofy5515
    @safeyyasofy5515 9 ปีที่แล้ว

    Thanks girl ! The best here 👏👏👏👏👏👍👍👍👍👍😙

  • @hiraktailor1916
    @hiraktailor1916 6 ปีที่แล้ว +1

    I m in love with your voice😀😀😆
    And yes this was very useful thanks!!!

  • @vijaykumar-bp4xb
    @vijaykumar-bp4xb 4 ปีที่แล้ว

    is lipid molecule separated with the help of gas exchange chromatography?????????????

  • @joshprichard9049
    @joshprichard9049 9 ปีที่แล้ว

    me to thanks got a test common up and this helped me :)

  • @sylvecakes8450
    @sylvecakes8450 8 ปีที่แล้ว +2

    Good drawings, but needs to concentrate and remember the speech

  • @emanabo-elmaaty8931
    @emanabo-elmaaty8931 3 ปีที่แล้ว

    Fantastic ❤

  • @theodoregoujon4017
    @theodoregoujon4017 8 ปีที่แล้ว

    so which substance is more polar? The one closer to the stationary or mobile phase?

    • @SantosAl
      @SantosAl 8 ปีที่แล้ว

      Theodore Goujon. depends on the the type of stationary phase/mobile phase you use.

  • @badranmohamed5772
    @badranmohamed5772 9 ปีที่แล้ว +1

    Than you very much for the help. the way you explained paper chromatography made it extremely simple. Again, thank you for such a video

  • @elizavethmogrovejo2472
    @elizavethmogrovejo2472 5 ปีที่แล้ว

    Helping me out for my regents today ☹️✅

  • @muhammadrizwan3309
    @muhammadrizwan3309 2 ปีที่แล้ว

    nice work keep it up

  • @Ersair
    @Ersair 11 ปีที่แล้ว +9

    5/5, would watch again

  • @sramtrain
    @sramtrain 8 ปีที่แล้ว

    where is this on the website?

  • @KonradKustosik
    @KonradKustosik 10 ปีที่แล้ว +37

    beautiful voice.

    • @yarakharam5343
      @yarakharam5343 7 ปีที่แล้ว +15

      are fucking kidding me she sound slike a 7 year old boy with a clogged nose. You must be some fucking omega-virgin.

    • @TheRayll
      @TheRayll 6 ปีที่แล้ว +11

      and this is why i love reading comments

    • @Abdullah-cj2mh
      @Abdullah-cj2mh 6 ปีที่แล้ว +4

      Nice Student idk why but "some kind of fucking omega-virgin" made my day

    • @TheRayll
      @TheRayll 6 ปีที่แล้ว

      ikr

    • @yarakharam5343
      @yarakharam5343 6 ปีที่แล้ว +3

      ty m8 I really felt it while typing

  • @kimdean2034
    @kimdean2034 2 ปีที่แล้ว

    I love it 😍

  • @kemjikaechebelem451
    @kemjikaechebelem451 7 ปีที่แล้ว

    thank you so much those extremely helpful!

  • @Mikeek7
    @Mikeek7 5 ปีที่แล้ว

    this was helpful. thank you!

  • @ellerose1844
    @ellerose1844 5 ปีที่แล้ว

    Does anyone have some videos I can use for science Olympiad

  • @TitusSupremus
    @TitusSupremus 9 ปีที่แล้ว +1

    10/10 ign
    most intrtuiging thing ever

  • @nickhon3396
    @nickhon3396 10 ปีที่แล้ว

    should choose a better pallette of colours, i couldnt read what you wrote in the hplc

  • @mounabaziz5906
    @mounabaziz5906 3 ปีที่แล้ว

    Thank youu

  • @vistian
    @vistian 2 ปีที่แล้ว +1

    You're going to cost people points on the MCAT with the misrepresentation of size-exclusion chromatography. The larger molecules elute first.

  • @MrHarun-dv6ee
    @MrHarun-dv6ee 8 ปีที่แล้ว +1

    Aren't the water molecules trapped WITHIN the cellulose fibres of the paper the stationary phase and NOT the paper itself?

    • @medschoolvideos
      @medschoolvideos 8 ปีที่แล้ว

      +Mamma Harun yh but it better to say the paper as the cellulose is needed to keep the water stationary

  • @jasmin8395
    @jasmin8395 7 ปีที่แล้ว

    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?

    • @InLostTime
      @InLostTime 7 ปีที่แล้ว

      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 :)

  • @vetaya4783
    @vetaya4783 7 ปีที่แล้ว +1

    Very good and simple explanation,thanks :))

  • @hasnathassan922
    @hasnathassan922 8 ปีที่แล้ว

    very nice

  • @zakariajony4193
    @zakariajony4193 8 ปีที่แล้ว

    Munna sir's advice.

  • @beckytonn5527
    @beckytonn5527 8 ปีที่แล้ว

    Love your pictures. They are GREAT: )

  • @masror_ah
    @masror_ah 2 ปีที่แล้ว +1

    2:04 that arrow is more beautiful than my whole life

  • @SaveeraKhan_Z
    @SaveeraKhan_Z 3 หลายเดือนก่อน

    The mobile phase is solvent or the spot that is on paper? Please someone clear my question 😢

    • @Zara-p5m
      @Zara-p5m 3 หลายเดือนก่อน

      Solvent

  • @gregorytaylor8809
    @gregorytaylor8809 2 ปีที่แล้ว

    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

  • @maithilipokle4437
    @maithilipokle4437 5 ปีที่แล้ว

    It's wrong. Paper is not the stationary phase. It's the water present in the paper. It's a liquid liquid chromatography.

  • @ilaiyarajaips6919
    @ilaiyarajaips6919 7 ปีที่แล้ว

    good

  • @preetimanoth1814
    @preetimanoth1814 6 ปีที่แล้ว

    What is cpillary action

  • @tirivokureangel4984
    @tirivokureangel4984 5 ปีที่แล้ว

    Nice

  • @amyz9170
    @amyz9170 9 ปีที่แล้ว +3

    is her nose blocked or something? but good video

  • @Rainyumz
    @Rainyumz 8 ปีที่แล้ว +1

    I find your voice so attractive

    • @erich3892
      @erich3892 7 ปีที่แล้ว

      Villainz YumzZ perv

  • @landoncochrane1030
    @landoncochrane1030 2 ปีที่แล้ว

    Hi fbi personnel I'm not makeing ricen I would die doing it and I have no uses for it

  • @ibrahim2ibrahim
    @ibrahim2ibrahim 10 ปีที่แล้ว

    guys, why is the solvent always under the pencil line (in paper and sillica plating)

    • @ibrahim2ibrahim
      @ibrahim2ibrahim 10 ปีที่แล้ว

      Snehaha1 oh ok awesome, thanks!