Organic Chemistry MCAT Problems: Separations and Purifications

[@chelseaa101]

Your videos are getting me through content review phase! Just completed the gen chem and organic chem playlist, thank you professor eman for all your hard work!

[@professoreman2289]

Omg this makes me soo happy to hear, I hope you ace the MCAT! Rooting for you!!

[@eseasoro7251]

Thanks a lot for this OChem playlist

[@professoreman2289]

Anytime!

[@deenguyen6286]

Thank you so much for everything :)

[@professoreman2289]

You are so welcome!💕

[@LuisaRodriguez-pd8wu]

Thank you so so much for this playlist! It was super helpful!

[@professoreman2289]

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[@professoreman2289]

Correction for 4: the correct answer to the question is Benzyl acetate (Option B), not Option D. Benzyl acetate is the least polar among the options provided, so it would elute first when separated by column chromatography using ether on silica gel. The order of elution is based on polarity, where less polar compounds elute first because they have weaker interactions with the polar silica gel. Benzyl acetate, being less polar than the other compounds listed, would move through the column faster and elute before the others. I’m sorry about this error and will refilm! ❤

[@shirminlim4217]

Hello! For question #4, why is it that Benzyl alcohol is not eluted 1st? Since it has the least solubility / affinity for ether, shouldn't it go through the column the fastest i.e eluted? Thank you! :)

[@professoreman2289]

Hi! Correction for 4: the correct answer to the question is Benzyl acetate (Option B), not Option D. Benzyl acetate is the least polar among the options provided, so it would elute first when separated by column chromatography using ether on silica gel. The order of elution is based on polarity, where less polar compounds elute first because they have weaker interactions with the polar silica gel. Benzyl acetate, being less polar than the other compounds listed, would move through the column faster and elute before the others. I’m sorry about this error and will refilm! ❤

[@medicalminutia]

I love these videos! Thank you for posting this one. When discussing polarity of solvents or eluents like for the problem you did, how did you know Ether is more polar than the less polar, Hexane? And where do we go to know what structures we have to learn and remember for the MCAT like Ether?

[@professoreman2289]

Thank you so much!! If you watch the whole playlist, nomenclature for various functional groups is discussed. In addition, hexane is a hydrocarbon (nonpolar) and ether has an oxygen (polar).

[@RA-pu9jo]

Girl, you're my angel You're my darling angel Closer than my peeps you are to me, baby Shorty, you're my angel You're my darling angel Girl, you're my friend When I'm in need...

[@professoreman2289]

thank you for singing to me ;)

[@RuthGoshu]

Can you explain how we were supposed to know that for #2?

[@professoreman2289]

There’s lecture videos associated with the problem sets