Basics of chromatography | Chemical processes | MCAT | Khan Academy

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  • čas přidán 16. 09. 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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Komentáře • 273

  • @metoo2here
    @metoo2here Před 10 lety +378

    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 Před 7 lety

      upvote so others see

    • @iansteinke2414
      @iansteinke2414 Před 6 lety +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 Před 2 lety

      Correct

  • @coreyking212
    @coreyking212 Před 8 lety +358

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

    • @remusomega
      @remusomega Před 8 lety +55

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

    • @sylvecakes8450
      @sylvecakes8450 Před 8 lety +2

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

    • @nathanbrown4689
      @nathanbrown4689 Před 7 lety +24

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

    • @sylvecakes8450
      @sylvecakes8450 Před 7 lety +2

      I did not type that it was my friend for reals

    • @saintofchelseathomascarlyl5713
      @saintofchelseathomascarlyl5713 Před 6 lety +3

      it was my friend

  • @CORPSE77
    @CORPSE77 Před 6 lety +22

    * 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.

  • @oliviadenyer-dobrowolski7441

    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!

  • @trilliumchang4127
    @trilliumchang4127 Před 8 lety +401

    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 Před 5 lety +2

      True that.

    • @peepdi
      @peepdi Před 5 lety +1

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

    • @hargobindsingh3167
      @hargobindsingh3167 Před 5 lety +3

      @@peepdi sorry was wrong here mixed a concept😅

    • @peepdi
      @peepdi Před 5 lety

      @@hargobindsingh3167 it's completely fine 😁

    • @robertsanchez4316
      @robertsanchez4316 Před 5 lety +8

      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

  • @EHBRod13
    @EHBRod13 Před 10 lety +79

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

  • @gemechubekele2546
    @gemechubekele2546 Před 8 lety +96

    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 Před 8 lety

      +Gemechu Bekele Yes.

    • @khadijahadam4387
      @khadijahadam4387 Před 8 lety +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

    • @pranavvariava2685
      @pranavvariava2685 Před 7 lety

      emeg losota yes

    • @VincentStevenson
      @VincentStevenson Před 6 lety +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 Před 2 lety +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

  • @TheSurvivalSecrets
    @TheSurvivalSecrets Před 10 lety +11

    That was extremely helpful, thanks!

  • @bushraduti6780
    @bushraduti6780 Před 10 lety +29

    extremely helpful :) love your voice :)

  • @kristak.1625
    @kristak.1625 Před 5 lety +1

    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.

  • @iqtidarrahman2148
    @iqtidarrahman2148 Před 9 lety +1

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

  • @anousharahimzada5837
    @anousharahimzada5837 Před 9 lety +2

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

  • @pablolobo2070
    @pablolobo2070 Před 6 lety +1

    Thank you, very informative!

  • @MrW0lfies
    @MrW0lfies Před 6 lety +1

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

  • @kemjikaechebelem451
    @kemjikaechebelem451 Před 7 lety

    thank you so much those extremely helpful!

  • @albertchen2020
    @albertchen2020 Před 4 lety +3

    Aww, her voice is so cute

  • @nonoooooooooo1
    @nonoooooooooo1 Před 9 lety

    u just saved my life thank you so much

  • @AKASHVERMA-ok2ns
    @AKASHVERMA-ok2ns Před 6 lety +4

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

  • @estrellasolimar9019
    @estrellasolimar9019 Před 7 lety

    thank you. this was very helpful.

  • @joshprichard9049
    @joshprichard9049 Před 9 lety

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

  • @hafsa1698
    @hafsa1698 Před 9 lety +135

    What happened to Sal's voice? 0_o

    • @WaddiaS
      @WaddiaS Před 8 lety +8

      It's a KA spin-off

    • @lovelybias
      @lovelybias Před 8 lety +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 Před 7 lety

      Ikr?

    • @audreyandremington5265
      @audreyandremington5265 Před 3 lety

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

  • @sadamalinimalaweera4528
    @sadamalinimalaweera4528 Před 3 lety +1

    Great video, super helpful thanks

  • @jore354
    @jore354 Před 9 lety +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 Před 8 lety

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

    • @naomik5213
      @naomik5213 Před 8 lety

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

  • @amanal-kabbani2745
    @amanal-kabbani2745 Před 2 lety +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!

  • @IIAmzazZ
    @IIAmzazZ Před 10 lety

    thanks helped alot!

  • @hanan2184
    @hanan2184 Před 2 lety

    this video made it make so much sense THANK YOU

  • @trilliumchang4127
    @trilliumchang4127 Před 8 lety +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 Před 5 lety

      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.

  • @safeyyasofy5515
    @safeyyasofy5515 Před 9 lety

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

  • @MrElectricSkittles
    @MrElectricSkittles Před 8 lety +101

    x1.5

  • @jansenlimawan8415
    @jansenlimawan8415 Před 6 lety

    Thanks, very helpful.

  • @Mikeek7
    @Mikeek7 Před 5 lety

    this was helpful. thank you!

  • @beckytonn5527
    @beckytonn5527 Před 8 lety

    Love your pictures. They are GREAT: )

  • @vivaanmaheshwari9852
    @vivaanmaheshwari9852 Před rokem +1

    yes you are right and like

  • @Chem4students
    @Chem4students Před 3 lety

    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.

  • @jasroop_sandhu
    @jasroop_sandhu Před 8 lety +10

    Beautifully Explained!

  • @aztec4194
    @aztec4194 Před 6 lety

    Nice video really helped before exam thanks you so much

  • @NAGAVERSE
    @NAGAVERSE Před 5 lety +7

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

  • @nerdykityplantchild6301
    @nerdykityplantchild6301 Před 10 lety +4

    This helped for science olympaid thanks!!

  • @DuongNguyen-ni9gz
    @DuongNguyen-ni9gz Před rokem

    excellently explained !

  • @ashrafazman2859
    @ashrafazman2859 Před 5 lety +1

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

  • @badranmohamed5772
    @badranmohamed5772 Před 8 lety +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

  • @lalithkishore4249
    @lalithkishore4249 Před 7 lety

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

  • @elizavethmogrovejo2472

    Helping me out for my regents today ☹️✅

  • @NK_2542_
    @NK_2542_ Před 2 lety

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

  • @ruoyingzheng1680
    @ruoyingzheng1680 Před rokem

    thank you for the great content.

  • @DuyenLe-kf7gj
    @DuyenLe-kf7gj Před 4 lety

    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

  • @roheenamurad2375
    @roheenamurad2375 Před 4 lety +1

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

  • @Bhupender855
    @Bhupender855 Před 6 lety

    Most underrated channel

  • @aronrohithsingh2730
    @aronrohithsingh2730 Před rokem

    Thank you so much

  • @swanqilcooledition6666

    Thanks this video helped me a lot!

  • @thilinaalagiyawanna3680

    Thank You very much

  • @nancy8202
    @nancy8202 Před 2 lety

    Very very helpful ❤️

  • @imShifa
    @imShifa Před 5 lety

    Thank you.

  • @suhanapandey2749
    @suhanapandey2749 Před 3 lety +1

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

  • @georgefloyd5078
    @georgefloyd5078 Před rokem

    her voice is so soothing

  • @gracysingh1737
    @gracysingh1737 Před 3 lety +1

    Thank you !! Extremely helpful

    • @prit0012
      @prit0012 Před 2 lety

      our comments look pretty young out here 🤣.once upon a time Khan Academy used to be a very popular educational channel

  • @sujanashwath9173
    @sujanashwath9173 Před 7 měsíci

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

  • @kimdean2034
    @kimdean2034 Před 2 lety

    I love it 😍

  • @gregorytaylor8809
    @gregorytaylor8809 Před 2 lety

    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

  • @ibrahimkhoja
    @ibrahimkhoja Před 3 lety

    Thanks a lot 🙏

  • @TheChessRobloxian
    @TheChessRobloxian Před 11 měsíci +2

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

    • @Philippine_Navyist16
      @Philippine_Navyist16 Před 10 měsíci +1

      same

    • @TheChessRobloxian
      @TheChessRobloxian Před 10 měsíci

      @@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 Před 10 měsíci

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

    • @TheChessRobloxian
      @TheChessRobloxian Před 10 měsíci

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

    • @Philippine_Navyist16
      @Philippine_Navyist16 Před 10 měsíci

      @@TheChessRobloxian yay he aprovves

  • @OMNI_INFINITY
    @OMNI_INFINITY Před 11 měsíci

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

  • @TitusSupremus
    @TitusSupremus Před 8 lety +1

    10/10 ign
    most intrtuiging thing ever

  • @mounabaziz5906
    @mounabaziz5906 Před 3 lety

    Thank youu

  • @emanabo-elmaaty8931
    @emanabo-elmaaty8931 Před 3 lety

    Fantastic ❤

  • @lauren9004
    @lauren9004 Před 9 měsíci

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

  • @xxxyyyyzzzzzzz
    @xxxyyyyzzzzzzz Před 4 lety

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

  • @hiraktailor1916
    @hiraktailor1916 Před 6 lety +1

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

  • @KonradKustosik
    @KonradKustosik Před 10 lety +37

    beautiful voice.

    • @yarakharam5343
      @yarakharam5343 Před 6 lety +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 Před 6 lety +11

      and this is why i love reading comments

    • @Abdullah-cj2mh
      @Abdullah-cj2mh Před 6 lety +4

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

    • @TheRayll
      @TheRayll Před 6 lety

      ikr

    • @yarakharam5343
      @yarakharam5343 Před 6 lety +3

      ty m8 I really felt it while typing

  • @princessvirina1649
    @princessvirina1649 Před 5 lety +2

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

  • @Ersair
    @Ersair Před 10 lety +9

    5/5, would watch again

  • @mukarrambutt453
    @mukarrambutt453 Před 3 lety

    In paper chromatography, the stationary phase is not paper but the liquid that is bonded upon it.

  • @sylvecakes8450
    @sylvecakes8450 Před 8 lety +2

    Good drawings, but needs to concentrate and remember the speech

  • @ishu9176
    @ishu9176 Před 8 lety +8

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

  • @muhammadrizwan3309
    @muhammadrizwan3309 Před rokem

    nice work keep it up

  • @mangatons
    @mangatons Před 8 lety

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

  • @mekhicampbell3226
    @mekhicampbell3226 Před 2 lety +1

    Thx ima make ricen now

    • @epic8924
      @epic8924 Před 2 lety

      Came here from the video too

  • @vetaya4783
    @vetaya4783 Před 7 lety +1

    Very good and simple explanation,thanks :))

  • @bansalpharmacycollege
    @bansalpharmacycollege Před 7 lety

    very good

  • @57.zoonabatool61
    @57.zoonabatool61 Před 3 lety

    Can u plz make a tutorial on ascending paper chromatographyy

  • @tahsinrahman1668
    @tahsinrahman1668 Před 7 lety

    so, the capillary action will take place in both?

  • @hasnathassan922
    @hasnathassan922 Před 7 lety

    very nice

  • @sramtrain
    @sramtrain Před 8 lety

    where is this on the website?

  • @floraacademics1195
    @floraacademics1195 Před 7 lety

    kindly add true expt. which would be easy to understand

  • @ellerose1844
    @ellerose1844 Před 5 lety

    Does anyone have some videos I can use for science Olympiad

  • @kidsandkids5687
    @kidsandkids5687 Před 2 lety

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

  • @sexyscientist
    @sexyscientist Před 7 lety

    You are explaining GC as if it is fractional distillation.

  • @theodoregoujon4017
    @theodoregoujon4017 Před 7 lety

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

    • @SantosAl
      @SantosAl Před 7 lety

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

  • @tirivokureangel4984
    @tirivokureangel4984 Před 5 lety

    Nice

  • @MrHarun-dv6ee
    @MrHarun-dv6ee Před 8 lety +1

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

    • @medschoolvideos
      @medschoolvideos Před 8 lety

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

  • @ilaiyarajaips6919
    @ilaiyarajaips6919 Před 7 lety

    good

  • @zakariajony4193
    @zakariajony4193 Před 7 lety

    Munna sir's advice.

  • @masror_ah
    @masror_ah Před 2 lety

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

  • @vistian
    @vistian Před 2 lety +1

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

  • @vijaykumar-bp4xb
    @vijaykumar-bp4xb Před 3 lety

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

  • @emon8506
    @emon8506 Před 6 lety

    danke

  • @jasmin8395
    @jasmin8395 Před 7 lety

    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 Před 7 lety

      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 :)

  • @soham85e52
    @soham85e52 Před 4 lety +2

    HELLO!

  • @amyz9170
    @amyz9170 Před 9 lety +3

    is her nose blocked or something? but good video

  • @Ghajlalalala
    @Ghajlalalala Před 2 lety

    TIME TO MAKE RICIN!