Recrystallization | MIT Digital Lab Techniques Manual

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Recrystallization
Recrystallization takes patience, but its worth it! This video walks you through the procedure, from solubility tests to cold filtration, with information on one-solvent and two-solvent recrystallizations.
Created by Dr. Sarah Tabacco and Aaeyesha Siddiqui
View the complete resource at: ocw.mit.edu/OcwWeb/resources/R...
License: Creative Commons BY-NC-SA
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WARNING NOTICE:
The experiments described in these materials are potentially hazardous and require a high level of safety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. Legal Notice - ocw.mit.edu/OcwWeb/web/terms/t...

Пікірлер: 44

@filmviewer7 7 жыл бұрын

Anyone else here because of ochem class? XD

@x0xxx007i 7 жыл бұрын

me lol

@twixxtwizz452 4 жыл бұрын

Yes, and corona lol

@mikkit876 3 жыл бұрын

yup, even 3 years later lol

@skiphoffenflaven8004 3 жыл бұрын

I would assume that to be the case, in general.

@97amani 3 жыл бұрын

anyone doing organic chem assignments for pearson mastering chemistry? email me at allen.amani97@gmail.com (incentive provided)

@Izaya_Orihara 3 жыл бұрын

Open transcript >> toggle timestamp >> copy & paste to Word >> ctrl + F keywords >> done with ochem worksheet

@micahkkipruto5336 3 жыл бұрын

Learning ,it’s very educative and resourceful. As Virginia Union University student I recommend this for you too

@sairamaritzacarhuayalalvar7645 3 жыл бұрын

This is very useful in pandemic times, because we aren't allowed to go to the laboratories! thank you :D

@vedmaburuxova68 Жыл бұрын

I had 2 lab courses simultaneously during 2 semesters of covid. We just had to put on a mask and get to it. Was horrible, couldn't see anything with the protective glasses fogging up haha

@prof.luizclaudio.barbosa 3 жыл бұрын

Excelent video on recrystallization.

@lssam100 12 жыл бұрын

Thank you Mit , THANKS .

@chemistmcg 9 жыл бұрын

don't forget to remove those boiling chips you added before allowing it to cool.

@Fraidoon 3 жыл бұрын

Thanos: Post the video his man: But sire! the quality Thanos: I said do it

@user-tv6ii8zl6v 3 жыл бұрын

Question : in the case of two solvent, what is the problem if I do first hot filteration for more purification if there are insoluble impurities suspended with my new copmound?

@RuthNaguaJ 8 жыл бұрын

como lo cambio al español?? ayuda porfavor

@playingguitarorange 13 жыл бұрын

THUMBS UP---IF you enjoyed the music accompanying the recrystallization.

@eliseeng1709 4 жыл бұрын

yesss

@ElSqualito 2 жыл бұрын

Choco bisettes

@alexdupuy5617 2 жыл бұрын

Ah ouais carrement

@ElSqualito 2 жыл бұрын

Ah oui mange moi la gestion

@thiennhinguyennguyen2456 3 жыл бұрын

Có ai ở đây vì môn practice organic không?

@ikeotoyeuzorma5222 2 жыл бұрын

Good luck

@QueenofCool 10 жыл бұрын

Why is it that the ideal solvent is insoluble in room temperature but soluble with the sample at boiling point?

@AgonyGlyph 9 жыл бұрын

You want all of the compound to dissolve in the solvent (= no crystals) at the point where the solvent would start to boil. But when you cool down the solvent the solubility decreases which leads to forming of compound crystals. When solution has cooled to room temperature you want all of your initial compound to be as crystals, and not dissolved in the solvent, for a maximum yield. Only the impurities should be dissolved in the solvent at room temperature.

@AmlanRayasingh 3 жыл бұрын

Henry law and roult law

@chunkymonkey2782 11 жыл бұрын

can someone explain more in depth why oiling out happens and what to do if it happens?

@Skunkhunt_42 6 жыл бұрын

Possible with any method, especially reverse additions. One possible cause of oiling out is that drops of the product solution are surrounded by the antisolvent, in which the solubility is very low, and this low solubility creates localized regions with very high supersaturation ratios. Many variables to consider here. Before mixing to the molecular level is achieved, the localized high supersaturation forces the product out of solution without allowing sufficient time for ordering of molecules to enable crystal development. The resulting oily particles have a tendency to clump together before the Occluded solvent migrates throughout the solution. As the mixture is aged, the oiled-out particles may transform into amorphous solids or become "crystalline" (with poor lattice structure)

@2MinTz2 9 жыл бұрын

chunkymonkey2782 If I understand correctly, oiling happens when the boiling point of the solvent exceed the melting point of the sample. So when sample is dissolve at boiling point of the solvent, the solution created would have the sample "oiled" out instead of crystallize out. If this happen, you should reselect your solvent...