Firstly, excellent demonstration. Can I please ask, why did you add a second layer of sand above the silica layer? When I perform chromatography, I never add a second layer. I just swirl my sample around the inner surface. Will it be advantageous to add a second layer of sand? Thank you
@@channychan3558 Wouldnt that be when you load sample first and then add the sand on top? I have seen a vid of someone demonstrating that. I dont know whether to load the sample before the sand or after the sand. Also should we load the sample through pipette by making a ring via pippetting along and around the glass of the column or dropping it straight down the center to form the band. I ask since I've seen it done here on RU-vid both ways. Just would like to know which is the common or preferred way.
If I have solid sample containing components, can I use any solvent to dissolve it? Or I have to use only the same mobile phase as solvent to dissolved sample? Another case, if must use same mobile phase, but my sample can not dissolve, here, please I need solution to this problem. can I use any solvent? thank you alot
thank you so much. Is there standard to use silica gel in column, I mean if my sample a little bit like (0.01 gram), how much of silica gel use here? in contrast, if I have a lot of samples such as (1 gram or more), here, how much of silica gel have to use? I mean is there ratio from silica gel to sample to use in column, please tell me
thank you. If I used wet packing of silica gel to column (slurry), here, can I use any solvent for silica gel until reached slurried, or same mobile phase or must use only hexane.
A year late... But You need to figure it out by trial and error, through literation, or educated guess. Your goal is to get your material dissolved but separated during the column/elution. If you use the extraction solvent, most of the time you will get terrible separation. To figure out what eluent combination is best, try to do Thin Layer Chromatography tests in a series of polarity (example: from 10:1 hex:EA to 1:2 ratio) and see the separations. Use the solvent with the best separation and Rf of your target compounds
True, and I'm not advocating for gloves in 100% of situations. Here though, she is being an example for students to follow. As a TA, I can tell you that students need reminding to wear gloves
Because it's FUCKING USELESS! Since the moment when I started the video I knew that there would have been some lab safety freak commenting about the gloves.
No reason to wear gloves for every single thing we do in the lab. If I am mixing up sugar solutions, I am not wearing gloves. For most things gloves are not necessary. Use your brain, do a little research before working with a chemical. Don't just automatically put ppe on if there isn't a a good reason to.
Have you guys ever worked with methylene chloride? It can do some damage to skin, and although you can wash it off and be fine, it is very uncomfortable for even brief periods of time.
Hi, I have a question. I want to Pack column with silica. Which solvent is better for packing of column with silica. Is water is ok? because in mobile phase i will use ethyl acetate and methanol.
