I wonder if that's because in the class we don't pay any attention, while in the exam session our dopamin/serotonin receptors suddenly get busy... Or some people are just charismatic while others, simply are not.
Panagiotis Atmatzidis No, I really do believe her explanation was simply great. My chemistry class had severely curved grading because everyone basically failed. I suspect that everyone did poorly because the professor was not good at lecturing. The professor was a wonderful and likeable person, but his lectures were bad. For example I got something like 50% on the final and received an A- in the course because the grading was adjusted so much. Everyone in that class had horrible grades. My test marks were usually 30-40% higher than the class average, but I still felt like nothing made sense in his class... I really did try hard and pay attention too.
I think this is wrong explaination! moved far: less polar, less attracted to the solvent moved not far: more polar, more attracted to the solvent solvent is polar.
yehudit wolfe No silica gel is polar. She even said that in the video. So they will use a non-polar mobile phase. They CAN switch those two.. but in this video that was the case
stationary phase: the plate with silica gel on it mobile phase: the solvent or mixture of solvents in a beaker draw a pencil line 10mm up on the plate. use a toothpick to dot the sample onto the plate put 9mm2 of the solvent in a beaker. place plate in beaker. add a lid. wait for the mobile phase to move, until it’s almost at the top. take it out and draw a pencil line where it got up to. use a uv lamp to see the results. parts that moved further were more attracted to the solvent- less polar. parts that moved less far were more attracted to the silica (which is very polar) - so they are more polar
THANK YOU! I have my organic chemistry lab this afternoon and the lab manual did not explain clearly what the TLC experiment was going to look like. I feel more confident now haha
Excuse me, do you know how to prepare silica gel to absorb moisture or silica gel to act as the stationary phase in thin layer chromatography. I need to prepare TLC plate by my own.
Mercedes Malone I have not gotten to that yet on my course but I belive it has something to do with weather the component is more attracted to the plate or the solvent if it is more attractedbto the plate It only moves a littel uf it is attraxted to the solvent it moves alot I dont really know feel free to correct me
+Mercedes Malone Rf value's can help determine which spot is more polar (lower the spot = more polar)... However, TLC spots may vary due to the size and shape of the molecule. So to simply say that a spot is "more polar" because its lower isn't necessarily 100% correct.
hyeballer actually Rf values tell you about the affinity of the solute to the TLC plate. A high Rf value means a lower affinity for the TLC plate and greater solubility in the solvent.
What if you use a polar solvent? Would that change the distance the spots travel? Wouldn't the nonpolar compound not travel as much because of the polar solvent?
Josh... Technically speaking, you can let it go to the top...as long as you remove it the moment it reaches the top. As Mary C stated, if you were to leave it a prolonged period the spots will continue to run up.
Silica, (SiO2)x, is polar due to the polarity exhibited between the oxygen and silicon atoms. The silicon atoms are more electropositive than oxygen, and oxygen atoms are more electronegative than silicon.
Why does she say nonpolar molecules are attracted to the mobile phase, when the mobile phase is at the bottom? Why does it travel up higher? If someone knows and could answer it'd be much appreciated!
The mobile phase has travelled up the TLC plate by capillary action - the purple line she drew on the top of the TLC plate inticates how far the mobile phase moved. The less polar molecule being more attracted to the mobile phase means it moved further.
+Arsank47 Okay, so your stationary phase would be the TLC plate, which probably uses silica. The mobile phase is the solvent you're using. I'm not sure about the others, but I'd guess the detection system would be calculation of the Rf values and comparing them to a database.
+VirgiliusRomanus She explained the polarity of the solvent briefly, but not a solvent that consists of compounds with different polarities. For example, you could have a mixture of 5 parts ethyl acetate and 95 parts hexane (hexane being nonpolar) as your solvent, which will affect the distribution of compounds on the plate. In this case, nonpolar compounds won't be attracted to the stationary silicone phase or acetate and will travel very high up the plate because of their affinity to hexane. Polar compounds won't likely move very far because 5 parts acetate isn't polar enough to break that adsorption to the silicone plating. hope that helped.
PrideofPitchers you make some interesting points, do you know anything about the affinity of aluminium backed microcrystalline cellulose thin layer plates during the stationary and mobile phase?
can chromatography work with extremely small concentration, ....for example if you're trying to separate something out that is in the parts per trillion range?
You explained TLC better than my university chemistry professor in half the time.
I wonder if that's because in the class we don't pay any attention, while in the exam session our dopamin/serotonin receptors suddenly get busy... Or some people are just charismatic while others, simply are not.
Panagiotis Atmatzidis No, I really do believe her explanation was simply great. My chemistry class had severely curved grading because everyone basically failed. I suspect that everyone did poorly because the professor was not good at lecturing. The professor was a wonderful and likeable person, but his lectures were bad. For example I got something like 50% on the final and received an A- in the course because the grading was adjusted so much. Everyone in that class had horrible grades. My test marks were usually 30-40% higher than the class average, but I still felt like nothing made sense in his class... I really did try hard and pay attention too.
I agree
@@panagiotisatmatzidis9972 haha true😆
@@novacrystalas is this professor from LA lol?
moved far: less polar
attracted more to solvent
moved not far: more polar
attracted more to silica gel
silica gel is very polar
I think this is wrong explaination!
moved far: less polar, less attracted to the solvent
moved not far: more polar, more attracted to the solvent
solvent is polar.
yehudit wolfe No silica gel is polar. She even said that in the video. So they will use a non-polar mobile phase. They CAN switch those two.. but in this video that was the case
@@jobis34 👍
oh boy, did you just save my ass
stationary phase: the plate with silica gel on it
mobile phase: the solvent or mixture of solvents in a beaker
draw a pencil line 10mm up on the plate.
use a toothpick to dot the sample onto the plate
put 9mm2 of the solvent in a beaker.
place plate in beaker. add a lid.
wait for the mobile phase to move, until it’s almost at the top.
take it out and draw a pencil line where it got up to.
use a uv lamp to see the results.
parts that moved further were more attracted to the solvent- less polar.
parts that moved less far were more attracted to the silica (which is very polar) - so they are more polar
THANK YOU! I have my organic chemistry lab this afternoon and the lab manual did not explain clearly what the TLC experiment was going to look like. I feel more confident now haha
The way my profesor explained was in such way I didn't understand at all. Your graphic really helped me, thank you
Clear and concise explanation. Thank you!
Im doing this in yr 12 chemistry and I was so confused, but this vedio absoloutly cleared TLC for me, perfect :D
Thanks for the help! Good for high school as well :P
You saved my time and made this concept crystal clear to me.. Thank you very much ☺☺✨
Oh god, I have an o chem test tomorrow, and this helped me so much..thankyou!
how did the test go?
@@comoplaysdestiny5106 lmao 2 years ago. I'm pretty sure she/he would've forgotten
Thank you so much! i have all my confusions cleared out!
Thanks khan academy for such alucid exploration
Perfect for F324
Thank you very much💕
Awesome explanation! Thanks!
Thank you! I am doing this for school :P ty :D
Thank you for the knowledge
You are a life saver ❤
Your Welcome 😁
an cutie tone
Wow
*An cute tone
@@reubenfernandes9917 a*
we can even use ninhydrine for visualization of spots
Aditya Sharma only for aminoacids
I realized in lab this morning that if you used letter-writing paper for TLC, you would literally have a "stationery phase"
fire.
THANK YOU! I hate reading my MCAT books, this helps
beautiful and effective explanation =)
Thank you so much you helped me a lot ❤
Usually like this channel but I don't think a simple topic could be explained with any more complexity than in this tutorial
thnks i got my all fundas clear...........
I can't say anything except WOW
Your voice to me is what the silica gel is to the polar compound :DD
very good video for study tlc chromatography
Could you do one on paper chromatography with a polar solvent?
thank you 😃
thank u sooooo much !!!
Excuse me, do you know how to prepare silica gel to absorb moisture or silica gel to act as the stationary phase in thin layer chromatography. I need to prepare TLC plate by my own.
thank you. this helped me a lot to get through my lessons. nice work, well done
Thank you! And can I ask what programme you use to record your voice and what you're doing?
Thanks!!
Amazing video❤
This piece was really simple and understandable. Thanks a lot. more insight to you, dear.
with this i can get passed for 3rd level homi bhaba 6th grade
Brilliant explanation. Very useful
I loved this explanation. thanks
what is the Rf ????
the Rf vale is the distance moved by the component or part of the original substance/ the solvent front the point the solvent moved up to. =)
so sad that most chemistry books dont cover this. how does rf value relate to polarity?
Mercedes Malone I have not gotten to that yet on my course but I belive it has something to do with weather the component is more attracted to the plate or the solvent if it is more attractedbto the plate It only moves a littel uf it is attraxted to the solvent it moves alot I dont really know feel free to correct me
+Mercedes Malone
Rf value's can help determine which spot is more polar (lower the spot = more polar)... However, TLC spots may vary due to the size and shape of the molecule. So to simply say that a spot is "more polar" because its lower isn't necessarily 100% correct.
hyeballer actually Rf values tell you about the affinity of the solute to the TLC plate. A high Rf value means a lower affinity for the TLC plate and greater solubility in the solvent.
thanks.
What an amazing voice
What's little spot there in stationary phase?
Hell ya baby i love TLC, especially the my 600lbs wife videos and sister wives
Thank you!
And now I know, finally.............. :")
GRACIAS
Helpful...
what are the methods or ways of separating plant pigments?? only TLC and paper chromatography ?? please I need help
You saved me!!❤
Thank you so much! :)
nice video! thank you :)
Please, I want the method of separation mixture of soluble acid and soluble phenols
You are amazing
thanks !!
Well explained!!!!
thank u
great!!
this was just perfect 😍
What if you use a polar solvent? Would that change the distance the spots travel? Wouldn't the nonpolar compound not travel as much because of the polar solvent?
it would be opposite effect
why is it called separation method isnt it just straight up detection
2020 and they are still hot
Thank u so much!! U literally saved my ass!
you know, it'd be real cool iof you didn't write in cursive
what's a spotter?
0:50
hindi me bhi kuj lessons banaye aap
why do u have to remove your plate just a little before it reaches the top and not just let it go all the way?
the components that you were trying to separate will end up all reaching the end and run off the TLC plate along with the solvent
Josh... Technically speaking, you can let it go to the top...as long as you remove it the moment it reaches the top. As Mary C stated, if you were to leave it a prolonged period the spots will continue to run up.
I think silica is non-polar???
Silica, (SiO2)x, is polar due to the polarity exhibited between the oxygen and silicon atoms. The silicon atoms are more electropositive than oxygen, and oxygen atoms are more electronegative than silicon.
isnt silica overall nonpolar tho...if its the stationary phase why did she call it very polar?
Good :)
God, ur lovely voice.... make me wanna.... thanks for ur great explanations :)
Why does she say nonpolar molecules are attracted to the mobile phase, when the mobile phase is at the bottom? Why does it travel up higher? If someone knows and could answer it'd be much appreciated!
The mobile phase has travelled up the TLC plate by capillary action - the purple line she drew on the top of the TLC plate inticates how far the mobile phase moved.
The less polar molecule being more attracted to the mobile phase means it moved further.
+Arsank47 That sounds more like Gas Chromatography?
+Arsank47 Okay, so your stationary phase would be the TLC plate, which probably uses silica. The mobile phase is the solvent you're using. I'm not sure about the others, but I'd guess the detection system would be calculation of the Rf values and comparing them to a database.
are you mentioning what happens when the solvent is polar or nonpolar??? You should. Otherwise this is an incomplete explanation.
Isn't the stationary phase always polar and the mobile phase always nonpolar?
AnetheronOriginal Yeah, I've learned a lot at my internship. Solvents, duh! Sorry, I'm only in my first year of high school so :P
+Lily Li In this type of chromatography, compounds with more affinity to the solvent will travel further along with the solvent.
+VirgiliusRomanus She explained the polarity of the solvent briefly, but not a solvent that consists of compounds with different polarities. For example, you could have a mixture of 5 parts ethyl acetate and 95 parts hexane (hexane being nonpolar) as your solvent, which will affect the distribution of compounds on the plate.
In this case, nonpolar compounds won't be attracted to the stationary silicone phase or acetate and will travel very high up the plate because of their affinity to hexane. Polar compounds won't likely move very far because 5 parts acetate isn't polar enough to break that adsorption to the silicone plating.
hope that helped.
PrideofPitchers you make some interesting points, do you know anything about the affinity of aluminium backed microcrystalline cellulose thin layer plates during the stationary and mobile phase?
damn this was a mess in my head before I find this video
can chromatography work with extremely small concentration, ....for example if you're trying to separate something out that is in the parts per trillion range?
MY FUCKING G. LOVE YOU
chromatography is pain
2ryri
ur voice is um idk how to explain
Thanks a bunch!, very informative (and of course, very sexy voice! ;-) )
A very simple explanation and to the point. Thank you!
thank you !
THANKS SM
very well explained . Thanks
Thank youuu
Thanks
Thank you!
Thank you
Thank you
Thank you
thank you