Column chromatography | Chemical processes | MCAT | Khan Academy

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  • เผยแพร่เมื่อ 16 ก.ย. 2013
  • Learn how to separate chemicals using column chromatography. By Angela Guerrero. . Created by Angela Guerrero.
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ความคิดเห็น • 55

  • @Tennisplayer123
    @Tennisplayer123 8 ปีที่แล้ว +187

    im way too immature for the word stopcock lol

    • @dinijay
      @dinijay 6 ปีที่แล้ว +1

      lol

    • @bodybybarnes3795
      @bodybybarnes3795 5 ปีที่แล้ว +9

      lol especially when she said "ramming it against the stopcock"

    • @citronvertsoap
      @citronvertsoap 4 หลายเดือนก่อน

      LMAO

  • @MaryGwozdz
    @MaryGwozdz 9 ปีที่แล้ว +47

    It would have been nice to know how the polarities of the molecules lead to them being separated as they ran through all of these different materials.

    • @easylearning981
      @easylearning981 8 ปีที่แล้ว

      +Mary Gwozdz In general, polar molecules elute more quickly than polar ones. This is because silica gel has polar character. On the other hand, if some apolar compound is adsorbed or covalently linked to silica gel, polar molecules will tend to elute first, as apolar ones will tend to interact intermolecularly with the surface of the covered silica.

    • @emlmm88
      @emlmm88 7 ปีที่แล้ว +5

      apolar molecules you mean.

    • @iansteinke2414
      @iansteinke2414 6 ปีที่แล้ว

      EASY LEARNING

    • @iansteinke2414
      @iansteinke2414 6 ปีที่แล้ว +9

      I think you have it a bit backwards

  • @midosala8049
    @midosala8049 8 ปีที่แล้ว +3

    Thank you, really helpful.

  • @conjiii8372
    @conjiii8372 9 ปีที่แล้ว +2

    Thanks, that was really helpful.

  • @kachingaaa
    @kachingaaa 10 ปีที่แล้ว +9

    Aw thank you so much, I'm a medical student but I'm in my 1st year and I'm excited to use this channel's videos for lab :D I also love her voice

    • @erich3892
      @erich3892 7 ปีที่แล้ว +1

      kachingaaa hook me up with your journals and notes so i can be a sucessful surgeon, ill send u my contact information

  • @AmenIamHotepRA
    @AmenIamHotepRA 10 ปีที่แล้ว +11

    It would have been nice for you to mention what type of solvents are normally used, and the specific reasons for using each. Great video nonetheless.

    • @paigec7596
      @paigec7596 4 หลายเดือนก่อน

      Go read some literature on it.

  • @gaiusdaniel4221
    @gaiusdaniel4221 8 ปีที่แล้ว +2

    thank you

  • @lfcforever
    @lfcforever 10 ปีที่แล้ว +36

    HAHAHAHAHAHA softcock 3:15

  • @TruthAndLoyalty
    @TruthAndLoyalty 10 ปีที่แล้ว

    Great video.

  • @smritisofia7691
    @smritisofia7691 3 ปีที่แล้ว +4

    Alright.. but can someone tell me if purification of compounds by column chromatography depends on length of column or on state of solvent?

    • @okoye.charles
      @okoye.charles 2 ปีที่แล้ว

      It depends on neither... Remember the seperation is mainly based on the seperation of immiscible and miscible liquids.

  • @dineshramgi9168
    @dineshramgi9168 9 ปีที่แล้ว +5

    It is good for child.

  • @puppypi9668
    @puppypi9668 6 ปีที่แล้ว +4

    Oh holy cow, your voice is amazing! :'D
    And the video is really great content too! :DD
    I wish I could learn all the things from you :">

    • @karterquentin8732
      @karterquentin8732 3 ปีที่แล้ว

      A trick : watch series at kaldrostream. Me and my gf have been using it for watching lots of of movies these days.

    • @kevinboone5015
      @kevinboone5015 3 ปีที่แล้ว

      @Karter Quentin yup, have been using Kaldrostream for since november myself :)

    • @christopherasher5564
      @christopherasher5564 3 ปีที่แล้ว

      @Karter Quentin yea, I've been using kaldroStream for years myself :)

  • @eludobudo
    @eludobudo 6 ปีที่แล้ว +9

    Why the sudden change to a robot at 0:07? Haha

  • @lilykeen6283
    @lilykeen6283 ปีที่แล้ว

    this saved my ass. thank you

  • @sccm100
    @sccm100 5 ปีที่แล้ว +4

    Orgo lab is a torture

  • @johnstephenson2430
    @johnstephenson2430 3 ปีที่แล้ว

    Shouldnt the level of the solvent be dropping?

  • @MrBeachwaves
    @MrBeachwaves 3 ปีที่แล้ว +1

    The explanation from flask 1 to 2 is confusing. I don't get why different bands are showing up. The explanation of the set up was clear, but after that I got lost.

  • @zarikhan1158
    @zarikhan1158 6 ปีที่แล้ว

    Is Mobile phase or solvent contain that mixture that need to get separate??

    • @abdullahshahnawaz6585
      @abdullahshahnawaz6585 5 ปีที่แล้ว

      No, the Mobile phase or the solvent is just itself... The Mixture ( as a whole itself) is added after the Solvent is poured into the Column...

  • @rathodmayur8714
    @rathodmayur8714 5 ปีที่แล้ว

    Can anybody please tell me , Why is ammonia vapor taken in spray of Rubinic acid in metal chromatography?

    • @sparkunavailable
      @sparkunavailable 5 หลายเดือนก่อน

      to detect the presence of metal ions on the chromatogram. Rubinic acid, also known as ammonium molybdate, reacts with metal ions to form colored complexes that can be visualized on the paper or thin layer chromatography plate. For example, iron (III) ions form a blue complex, copper (II) ions form a green complex, and nickel (II) ions form a brown complex. Ammonia vapor helps to stabilize the complexes and enhance the color intensity.

  • @Troncannone
    @Troncannone 3 ปีที่แล้ว +1

    viva la delinquenza

  • @jrfw96
    @jrfw96 9 ปีที่แล้ว +2

    Sound m9

  • @tylercantrell3379
    @tylercantrell3379 10 ปีที่แล้ว +1

    What is the purpose of adding the sand?

    • @AmenIamHotepRA
      @AmenIamHotepRA 10 ปีที่แล้ว +1

      The sand is used primarily for the purpose of filtration.

    • @KevDawg673
      @KevDawg673 10 ปีที่แล้ว +5

      The sand also acts as a bed support for the column bed, supporting whatever resin/gel is being used for purification. This is why she stresses making sure it winds up horizontal; a crooked bed support will cause a crooked column and give poor purification, which she demonstrated.

  • @sabahiqra8708
    @sabahiqra8708 5 ปีที่แล้ว +1

    Is Sunny leone speaking? :3

  • @leehiufung911
    @leehiufung911 3 ปีที่แล้ว +3

    I am currently a PhD student in medicinal chemistry, and the very first thing that she says, is not really true. Chromatography is a terrible method to purify very large quantities of compound. Pharmaceutical companies need to be producing tens or hundreds of kilograms of compound, for a compound that is approved or in clinical development. Column chromatography is far too wasteful, in terms of the cost and environmental impact of the solvent and the silica gel. Crystallization is the preferred method, for drugs/compounds that have to be made in large quantities, in general. Now that isn't to say chromatography is useless. Usually, it is the method of choice when doing drug discovery initially, when far less of one particular compound is made (less than 10g, usually 50-100mg is enough), but many compounds need to be made and tested. Chromatography is also used as an analytical technique (HPLC-MS for instance), which can tell you how pure something is (kinda), for instance.

  • @Chelssums
    @Chelssums 4 ปีที่แล้ว +3

    i do not think this video was very helpful. There was no explanation of how and why they separate as well as the purpose of all of the "filters".

  • @vlogvines1718
    @vlogvines1718 3 ปีที่แล้ว

    Khan GS research center q😂😂

  • @rojafx
    @rojafx 9 ปีที่แล้ว

    1:01 you sure you know how to spell clock right?

    • @ibrahimfataw2352
      @ibrahimfataw2352 9 ปีที่แล้ว +19

      Stopcock not clock rojafx

    • @erich3892
      @erich3892 7 ปีที่แล้ว

      rojafx this is why kids shouldnt be fucking teachers, sal needs to get off his rich ass and help us

  • @ShenelleTaylor
    @ShenelleTaylor 8 ปีที่แล้ว +1

    thank you

    • @user-wx8kz7os7d
      @user-wx8kz7os7d 7 ปีที่แล้ว

      Shenelle Taylor I luv u

    • @Marcos-qn2ff
      @Marcos-qn2ff ปีที่แล้ว

      @@user-wx8kz7os7d me more

    • @citronvertsoap
      @citronvertsoap 4 หลายเดือนก่อน

      no me more@@Marcos-qn2ff