Gas chromatography | Chemical processes | MCAT | Khan Academy

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  • Опубликовано: 18 ноя 2024

Комментарии • 184

  • @hollywoodbb
    @hollywoodbb 2 года назад +118

    I’m a chemist and use multiple GCs every day. In my line of work, we’re more interested in how MUCH of a compound is in a sample rather than trying to identify a compound. But we also do look for the presence of a compound in certain scenarios. GC is excellent for both applications.
    To all you students, YES you will actually use these everyday if you go down a chemistry route. Familiarize yourselves with them. In my lab, titrations are also pretty prevalent as well as spectrometry and moisture analysis. A lot of it is automated which is a breeze, but we do manually perform some of these techniques.
    Chemistry is MUCH harder in college than in the field and I know how defeated I felt at times as a student. Hang in there and stay on the path! I enjoy my job now and at 26 I made 6 figures this past year. It’s worth it, I promise!

    • @pearlz4796
      @pearlz4796 2 года назад +4

      how far did you get into your education?

    • @hollywoodbb
      @hollywoodbb 2 года назад +9

      @@pearlz4796 I completed a 4 year degree and got my Bachelor of Science in Biological Science.

    • @NewWesternFront
      @NewWesternFront 2 года назад +4

      How did you secure employment?

    • @lorechadominic4920
      @lorechadominic4920 Год назад +1

      Thank you😅

    • @hollywoodbb
      @hollywoodbb Год назад +11

      @@NewWesternFront I knew the company was hiring and just submitted my resume and the company had 2 people leaving, so they were in need of replacements. And I did really well in the interview. A lot of times it’s just timing, too.
      Tips: Really polish your resume and spend some time curating it. If you can get past that first step, then you can really shine at the interview! Before you go into the interview, look up facts about the company and familiarize yourself with it. In my interview, the first question was, “So tell us what you know about the company?” And luckily I was able to speak for a minute or so about them, which they seemed to really like. It shows that you’re invested and aren’t just going to say, “idk I just want a job.” Also, knowing someone in the field definitely helps if you have that luxury. If you’re still in school, make sure to network and stay on good terms with your professors. A recommendation can go a long way.
      Oh and lastly, to my surprise, they hardly touched on chemistry in the interview. Most places just want you to have a basic knowledge/education of the field, then they’ll train you on the job the way they want. I think the only chem related question they asked me was which techniques I was familiar with. I basically just rattled off the analyses I had done in my labs (titrations, GC’s, capillary action, pH, etc.) and they essentially told me the main ones I’d be doing, and they would train me on the specific instruments. They mainly wanted to know how I work with others, if I can provide attention to detail, am I teachable, etc.

  • @hayley0Lewis
    @hayley0Lewis 10 лет назад +345

    Explained a million times better than my lecturer in a fraction of the time...thank you

  • @NathanielIReiff
    @NathanielIReiff Год назад +6

    10+ years out of high school and I’m still using the Khan Academy!

  • @henriklarsen8193
    @henriklarsen8193 8 лет назад +90

    You're doing a marvelous job, even at making chemistry sound adorable (the baby / sumo part)!

  • @korykubasek347
    @korykubasek347 11 лет назад +67

    khan academy has made my college life so much easier keep it up!

  • @elvinhasanaj9849
    @elvinhasanaj9849 2 года назад +11

    You saved me big time with this video. The explanation was clear and straight to the point summarized 50 textbook pages in 8min. I love u guys.

  • @sbmuthuraman
    @sbmuthuraman 10 лет назад +20

    Gas chromotography was explained in a simple manner and in detail covering most of the aspects of GC.

  • @syu11079
    @syu11079 9 лет назад +18

    great video! before stumbling on this video i spent ages reading textbooks, but still didnt quite get GLC. but your video explained it perfectly, so thank you! :)

  • @simflorianwilliam8617
    @simflorianwilliam8617 10 месяцев назад +1

    The only good thing about this channel is, I always like the video before playing it, iam loving gas chromatography now 😊

  • @1987crfe
    @1987crfe 3 года назад +5

    This was sooooo easy to understand. Crisp and Clear! Thanks a ton!

  • @andreac.5596
    @andreac.5596 4 года назад +5

    Thank you! I knew a little bit about GLC, but never really understood the carrier gas, mobile and stationary phase. I appreciate you so much for explaining this in detail!

  • @jamesperry4470
    @jamesperry4470 10 лет назад +9

    Good video, but I think it would be good to mention adsorption and why it is a fundamental concept in chromatography and the separation of the mobile phase by their polarity. This would help touch more on the uniqueness of the electron distribution (like if you looked at an electrostatic electron density map) and help communicate how unique each molecule really is when looked at through the means of any system of chromatography

  • @basheeranwar9058
    @basheeranwar9058 10 месяцев назад +1

    thank you so mush , I hope that you explain more topics that related to the chemical engineering

  • @mithili3906
    @mithili3906 9 лет назад +26

    Your handwriting is fancy

  • @marlonhowe7592
    @marlonhowe7592 11 лет назад +7

    This is awesome (-: I always use English explanation videos for Chemistry, as in German there just aren't any videos which combine theory and "fun" (?) as much as you have with the example of the sumowrestler. Really nice, thank you. (-:

  • @Marawan
    @Marawan 4 года назад +1

    this explanation just summed an entire part of my syllabus in only 8 minutes! Brilliant!

  • @kavitaselvaraj3216
    @kavitaselvaraj3216 9 лет назад +7

    So informative and easy to understand. Thanks.

  • @Simis999
    @Simis999 9 лет назад +6

    Such a friendly way of explaining, thanks a lot :)

  • @J_just_J_yes
    @J_just_J_yes 10 лет назад +6

    This is a great video, i'm doing a lab report about my gas chromatography and are not sure about what is actually going on for discussion sake's. Now i feel i have a better idea how to explain my data and reason it! Thanks! :)
    P.S. and the girl's voice is helpful in making sure males(such as myself) are still glued to the video till the end XD

  • @rutabnoor4285
    @rutabnoor4285 3 года назад

    Ahh atlasttt i found you ... Very thankful

  • @joylynjake4268
    @joylynjake4268 3 года назад +1

    I'm prepared for my chem lab thank you 🙏🏼

  • @lovemymonkey05
    @lovemymonkey05 9 лет назад +3

    I wish I had found your videos when I was still in college.

  • @yhpk9013
    @yhpk9013 11 месяцев назад

    Well explain! Thank you so much, I finally can understand the GC.

  • @Zetarrino
    @Zetarrino 8 лет назад +6

    What about the different polarities of the mobile versus the stationary phase? The substances within the compound that have the opposite polarity of the mobile phase will have traveled slower than the the ones with the same polarity due to attraction/repulsion.
    Would have liked a little more information about this.

    • @easylearning981
      @easylearning981 8 лет назад +2

      +Zetarrino Hello. Usually, if memory does not fail me, you can NEGLECT intermolecular forces in gas phase for many purposes. So compounds having lower boiling points will just flow within the gaseous inert stream, whilst those with higher boiling points will stay liquid for longer (not necessarily interacting with the liquid stationary phase). What really matters here is that substances with higher boiling points, as long as they stay liquid, will not be able to "flow with the wind", at all. :-) Anyway, I think your question is very worthy. For example, if bigger apolar molecules are mixed with smaller polar molecules. The latter ones were supposed to boil first, but due to interaction with the stationary phase, they do not. Maybe that would invalidate the result somehow.

    • @andrewk7470
      @andrewk7470 8 лет назад +1

      "flow with the
      ...
      we will never know.

  • @msiloveme16
    @msiloveme16 3 года назад

    Very clear, slow and steady! thanks

  • @bakhodirjonkakhkharov344
    @bakhodirjonkakhkharov344 2 года назад

    Sal Khan is Elon Musk in education! Thanks for this amazing platform

  • @trevorndhlovu7834
    @trevorndhlovu7834 4 года назад

    Fantastic staff my lady it's COOLSOME,I owe you one.

  • @arunimachakraborty6423
    @arunimachakraborty6423 8 лет назад +9

    I can't thank you enough for this. Bless you. :D

  • @prashanthraju4013
    @prashanthraju4013 6 лет назад

    Nice explanation. You said that sample separation in the column ( stationary phase ) is based on the boiling point & molecular size of the solutes present in the mobile phase. Actually it also depends on the polarity also.
    For example
    1. Polar stationary phase & polar mobile phase has more retention time
    2. Polar stationary phase & non ploar mobile phase has no interaction so sample in the mobile phase moves faster, lesser retention time.
    If it's not correct plz ignore my comment.
    Thanks for ur superrr explaination.

  • @anounymous7988
    @anounymous7988 2 года назад

    You're amazing god bless you 💖💖💖💖

  • @cindycho2933
    @cindycho2933 2 года назад

    Very helpful, thanks!

  • @maansaab987
    @maansaab987 11 лет назад +4

    loved your voice

  • @umawww
    @umawww 7 лет назад

    thank god this channel exist

  • @smthgsmthg1717
    @smthgsmthg1717 3 года назад

    Thankyou. You explained very well.

  • @prateekgupta3454
    @prateekgupta3454 8 лет назад +1

    amazing explanation

  • @awesomemangoes8072
    @awesomemangoes8072 5 лет назад +1

    Thank you

  • @guyweizman3791
    @guyweizman3791 3 года назад

    Perfect explanation!!!

  • @simplestatic3751
    @simplestatic3751 2 года назад

    I used the Hewlett Packard 5710a dual-column gas chromatograph with a flame analysation detector.

  • @MsRamy92
    @MsRamy92 3 года назад

    Great video!!

  • @chem-issatwait9528
    @chem-issatwait9528 2 года назад +1

    Sumo wrestler yeah understood thanks!

  • @seluffhello873
    @seluffhello873 8 лет назад +1

    What if a small compound with high boiling point and a bigger compound with low boiling point is in the mixture? Would that mean that more or less, they would travel at the same rate and will produce only 2 waves in your graph instead of 3?

  • @josyzong7919
    @josyzong7919 6 лет назад

    A good video!!! A lot better than my professor. Clear and easy to follow the logic.

  • @demetriosgianitsas9008
    @demetriosgianitsas9008 7 лет назад +1

    You literally saved my day, great explanation thank you very much!!!

  • @MadanKumarLakshmanan
    @MadanKumarLakshmanan 7 лет назад

    Excellent video. Very clear & informative. Sincere thanks.

  • @charlottebikech
    @charlottebikech 10 лет назад +5

    your voice sounds so much like leighton meester's

  • @obinnaduke
    @obinnaduke 6 лет назад

    You're awesome... Thank you so very much

  • @johngrantner7240
    @johngrantner7240 7 лет назад

    So good. You kick ass. This made it so much easier to understand

  • @btslovers9788
    @btslovers9788 4 года назад

    I love your videos.
    So elaborate!

  • @aboodqashoo4113
    @aboodqashoo4113 6 месяцев назад

    And, The affinity is an important factor of separation

  • @mohamedmamdouh4782
    @mohamedmamdouh4782 4 года назад

    I have one question regarding the temperature of inlet that is around 200 degree then sample is vapourized. After that it is introduced to column via carrier gas. Temperature in oven is ramping starting from might 30 till 220. The question is from high temperature of the inlet to slightly low oven temperature might lead a kind of condensation, how the sample still in vapour state during it 's journey to column. Plz illustrate.

  • @sudeepm6484
    @sudeepm6484 3 года назад

    what if the difference in the boiling points is not much and the sizes of the molecules of both compounds are also nearly equal? Do the peaks overlap? How to distinguish in such cases?

  • @Alicia-dm6yb
    @Alicia-dm6yb 8 лет назад

    awesome video..very well explained...

  • @digvijayyamagekar7139
    @digvijayyamagekar7139 6 лет назад

    Thank you so much !!!
    I got the idea now .

  • @akram4139
    @akram4139 5 лет назад

    Thanks so much

  • @lucyaudrey733
    @lucyaudrey733 9 лет назад

    very nice thank you

  • @lifeofastudent...317
    @lifeofastudent...317 Год назад

    What if it as similar boiling point and size? How can we distinguish it?

  • @unknownknown7427
    @unknownknown7427 3 года назад

    Superb 👍

  • @dan.6398
    @dan.6398 10 лет назад

    Absolutely great way of expanations. I coudn`t find anything better. Thanks ;)

  • @DuongNguyen-ni9gz
    @DuongNguyen-ni9gz Год назад

    excellent

  • @hayaalmly6083
    @hayaalmly6083 4 года назад

    Thank you! you made it so easier to fathom even for a 7 year old boy!!

  • @fitnesswe
    @fitnesswe Год назад

    phenomenal

  • @stephanieme4405
    @stephanieme4405 4 года назад

    If my doctor asked for it could he test for my prescription drugs Cymbalta and Lamictal Respridone or and others to make sure I was taking them or to see how much of them was in my system to affect other drugs I was taking?

  • @mustafabasim684
    @mustafabasim684 8 лет назад

    Great job

  • @jenishbarot7171
    @jenishbarot7171 6 лет назад

    thank youuuu......perfect explaination.

  • @eiliannoyes5212
    @eiliannoyes5212 3 года назад

    That's how you do it!

  • @xClaireW
    @xClaireW 10 лет назад

    great explanation!

  • @turkishgamernl8047
    @turkishgamernl8047 9 лет назад +1

    hi, im a student and i have a question about the boiling temperature.
    why is it that the one with the higher boiling point is going slower and adsorbs better and the other with the lower boiling point is faster and adsorbs badly? is there a reason for or is it just a rule you have to know about gas chromatography?

    • @prakharawasthi7062
      @prakharawasthi7062 9 лет назад +1

      more boiling point lesser it will be volatile, it will bind to liquid surface of column

    • @agent475816
      @agent475816 8 лет назад +1

      +Turkish GamerNL If it has a high boiling point, that means that it prefers to stay as a liquid compared to a gas that has a lesser boiling point.

  • @syamkumar6075
    @syamkumar6075 10 лет назад

    GasChromatography was explained in a simple manner and in detail covering most of the aspects of GC.

  • @jitendralodha13
    @jitendralodha13 10 лет назад

    thanks a lot.

  • @omymamohamed29
    @omymamohamed29 4 года назад

    Excellent 💜👏

  • @boringgrass
    @boringgrass 9 лет назад

    wow nicely explained

  • @kayleighprice9637
    @kayleighprice9637 7 лет назад

    Thanks again!

  • @365messiah
    @365messiah 7 лет назад

    Great informational

  • @samulasaidireddy
    @samulasaidireddy 9 лет назад

    kindly explain of oven track in Gas chromatography

  • @MrBlash93
    @MrBlash93 9 лет назад

    Great explanation. Thank you for your video

  • @razo786
    @razo786 11 лет назад

    Thanks.

  • @daindelucia7033
    @daindelucia7033 6 лет назад

    It looks like that, in your graph, time increases toward the origin.

  • @anghaitruyen240
    @anghaitruyen240 8 лет назад +1

    Would you like to tell me what program you used in your clip?

  • @Lagos08
    @Lagos08 8 лет назад

    Thank you very much for the explanation

  • @azagoodwin5899
    @azagoodwin5899 9 лет назад

    great simplified video ./.... i need more information for which type of substances can we use this technique for? e.g drugs and also what does the height of the peak tells us

    • @easylearning981
      @easylearning981 8 лет назад

      +Aza Goodwin The height of the peak informs the intensity. The more molecules reach the detector, higher the peak.

  • @videogrillo
    @videogrillo 4 года назад

    Shout out to one of the best explanations. Congrats Angela, smooth and clear. Indirectly I learned that GC is very destructive and I won't have a sample afterwards

  • @IIAmzazZ
    @IIAmzazZ 10 лет назад

    really helpful thanks

  • @kennytzz4073
    @kennytzz4073 7 лет назад

    Thank you!!!! u saved me !!!

  • @Muik69
    @Muik69 9 лет назад

    Simple and great explanation thanks!

  • @josephchong783
    @josephchong783 6 лет назад

    Your voice is amazing

  • @Everyonecallsmesophie
    @Everyonecallsmesophie 2 года назад

    I love you so much. I really do

  • @shaheenmalick5999
    @shaheenmalick5999 10 лет назад

    Does anyone who is taking the MCAT know if Mass Spec will be tested?

  • @80amnesia
    @80amnesia 10 лет назад

    neat, thumbs up

  • @dannytitus1645
    @dannytitus1645 6 лет назад

    this was really great. Thank you :)

  • @aliimadyounis2056
    @aliimadyounis2056 5 лет назад

    Thank you ❤️

  • @minjinoh4998
    @minjinoh4998 10 лет назад

    Big help

  • @NileshPatil-sn5lj
    @NileshPatil-sn5lj 10 лет назад

    nice video.like it.

  • @bushrayousef8766
    @bushrayousef8766 8 лет назад

    awesome video! thank you :) x

  • @shannondove96
    @shannondove96 8 лет назад

    What about using liquid chromatography for complex mixtures like milk or sewage? They would contain a wide range of things including but not limited to : small suspended solid particles, small suspended droplets of fats and oils , ionic stuff such as potassium, sodium, and chloride ions , proteins , and on and on.........what would happen if you run that through a chromatograph?

  • @marebearzzz027
    @marebearzzz027 10 лет назад

    this is great!!!!!!!!

    • @M7MD1712519
      @M7MD1712519 10 лет назад

      راجعي وخلي التعليقات عنك موب نافعك عند رياض هههههههههههههه

  • @kingoffunny1747
    @kingoffunny1747 9 лет назад +26

    Why does it sound like more than one person is speaking?

    • @DreadnaughtyArt
      @DreadnaughtyArt 9 лет назад

      King Of Funny The microphone volume keeps changing.

    • @michaelbowe1485
      @michaelbowe1485 9 лет назад +27

      King Of Funny Multiple personality disorder

    • @MightyOwl_01
      @MightyOwl_01 9 лет назад +1

      +King Of Funny In my classroom ppl are watching without headphones and all i can hear is blah blah blah lol, i cba to get my headphones so i just used subtitles

    • @Syeal7
      @Syeal7 6 лет назад +1

      I think parts of the recording was edited over with additional comments or corrections in which the original "tape" lacked. So the different volumes are actually recorded during different times.

  • @prashantprajapati5709
    @prashantprajapati5709 6 лет назад

    I have a doubt regarding the separation of the compound, suppose you have 2 compound one is lighter and have high affinity towards the stationary phase and the other compound which is heavier and have low affinity towards the stationary phase and the sample which contains both the compound is run in the gas chromatography then which compound will move out first?

    • @Shahram19702010
      @Shahram19702010 3 года назад

      That’s why methods development is very crucial. Temperature ramp will resolve your problem.

  • @at8736
    @at8736 5 лет назад

    Thank you. My lab TA sucks.

  • @bartacomuskidd775
    @bartacomuskidd775 5 лет назад

    how often does this need to be recalibrated? can a civilian run a GC using only the device manual?

    • @crychan
      @crychan 5 лет назад

      Bartacomus Kidd in the lab i work in, we run blank standards every 5 or 10 tests to ensure proper calibration and detect outliers

  • @dynamicguy2393
    @dynamicguy2393 8 лет назад

    this is all theory. please, can show as some real time videos on this, any way, I appreciate your effort