Recrystallization
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- เผยแพร่เมื่อ 9 ม.ค. 2020
- Now that we have covered a variety of separation techniques, we know how to get an isolated product! But if it's a solid, it may contain impurities. Recrystallization is a common organic chemistry laboratory technique for the purification of solids, so let's learn how to do it!
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Thank you very much for the video, I'm using this method in my organic chemistry lab. but most explanations went much more in depth than I needed and I had harder time understanding how this process worked than was necessary. This helped me quite a bit.
Thanks! Engaging videos for my college lab students since we are virtual.
thankyou so much for such a nice explanation as I m preparing for my practicals so it helped me a lot
This was useful for quickly remembering how to do something I learned how to do last semester.
Thank you so much for breaking it down to the basics! ^^
Thank you! That was so informative and straight to the point
Could you explain me how to get MCT oil from cocunut oil ?
Step by step....
Having my lab test tomorrow life saver 🎉thank you very much!
Thanks for video. Very helpful before my practical exam, so to remind me how it all works. Thanks a lot.
thank you so much! i am reviewing for my practical exam and this video helped me a ton :)
You saved me for my lab practical tomorrow!!!
You are phenomenal
OMG THANK YOU!! This is perfect
thanks man this really helped!
Can u pls tell me how to separate the small qty of compound in mother liqour which didnt form crystals but was supposed to??
I have an exam in this tomorrow! So thanks pro
Tnx so much I gone using this method in my exam😍😍
Thank you sir.
Thank you very much !
Is it necessary to cover the beaker containing the benzoic acid solution while cooling down?
Thank you sir
Thanks, sir 🌹
Thanks!
THANK YOU, MAN, my manuals are mystery novels. I always wanted to know why dissolve at high temp but not at low temp, so what i got from this is that at low temperature, the solid is supposed to crystalize, and at high temperature it's supposed to dissolve. And that the impurities should dissolve at room temp so they stay dissolved and don't precipitate. Am i wrong?
What solvents can be used?
thank you
I like watching your vids,you are very intelligent
What day this month will you do Woodrow Wilson
Is sugar crystal with thread on it. Is a result of cooling or evaporative crystallization????
how did you remove the impurity? did they just evaporate? or did you phyiscally remove them?
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Can it also removes Colour ?
thanks king
Phthalimide is recrystallize in which solvent ?? Sir.
If i had a pill or other form of some medicine, can i crystalize it like this or is anything going to crystallize?
can we use water as a solvant here? I want to make that experiment
Basically a summary of practical 10 pretty much, in a level Edexcel chemistry
But yeah the practical is preparation of a pure organic solid and test of its purity and then the second part of it is preparation of a pure organic solid
Dmt
thanks boss
the choice of the solvent will be based more on the identity of the impurities? So they will not recrystallize again with the pure solid?thank you
Solids usually have different temps that they crystallize at. Know your temps for the main ingredient you want to keep and your problem is solved
Thanks
thank you chemistry jesus
What happens if you cool it down too quickly?
Bagus bang videonya, makasi 😘
Sir, My crude extracts from bacteria but it's dissolved only In water pls tell me what can I do sir
Hello, so hot solvent is used to wash the recrystallized product in the filitration step?
Use cold solvent to wash away any impurities from the recrystallised product without dissolving it.
No that would dissolve it again and it would go through the filter 🤦🏼♀️ you want to keep the crystals on the filter
Could you explain me how to get MCT oil from coccunut oil..?
Step by step ..
Wich method..
You first have to go find the literature on that product and identify it's properties. If it's an oil then a non polar solvent is often good enough, but some behave differently when it's an organic vs inorganic solvent, so that may be important. So after choosing the best available solvent then try to identify other components that may carry over with it, and the properties of those to see which can be separated with the methods available.
I'm not familiar that compound so I can't tell you a specific method.
❤️❤️Love from India 🇮🇳🇮🇳
If the impurities are able to interrupt the lattice structure during the original precipitation, why aren't they also able to during the second step
Because they aint as gangster lol
Was thinking the same.
Sir,is it is mandatory to dry the crude product completely before recrystallization,which i want to recrystallized?
No. The general principle is just reducing the solubility to a point where the solvate is less soluble than the impurities. Crystalization of the appropriate product is best as a first step where it applies, but not all products crystylise in the same fashion or even in a practical means.
One such method is dissimilar separation, where you use two different solvents that won't mix, but the product and impurities are more attracted to one than the other. This is usually a method to separate organic and inorganic molecules, but is also useful between polar and non polar molecules.
I am trying to make 3 Nitro phthalic acid, but during the purification the crystals doesn't get formed as we expect. The. Crystal sizes are pretty smaller than the standard ones. Please help.
Drop strings into the solution and let them form onto the string
Thanks! My question is, is possible to recrystallise without heating a solvent?
Yes, evaporative
Yes, there are a few ways, but it depends onr he properties of the solvate. As someone said evaporation of the solvent is one method, which requires either heating or dehydration by some method. One method is to add a solution of another chemical that has a higher affinity with the solvent than the product, and that will reduce the solubility of the product and cause it to crash or precipitate out, although requiring additional purification steps.
Why is it necessary for the solvent to have low solubility at room temperature? can someone please explain
So that the product will precipitate again. Otherwise it will just stay in solution and you can't collect it.
@@ProfessorDaveExplains thank you! that makes it clear.
It's not necessary, it's just taking advantage of the fact that solids have specific solubility that correspond with temperature. "Room temperature" is just a standard reference like zero is between 10, and -10. For example, chlorates have a very low solubility versus chlorides at 0°C, which is much lower than room temp. On the other hand oxides may have no solubility until say 1,500°C. It just depends on what you're trying to do, but most crystals are nitrates, sulphates, or chlorides, and those are easiest to manipulate at 25°C (room temp).
Good
do you have any videos on basic chemistry? because I don't really know sht
Yes, watch my general chemistry playlist from the beginning.
ما عبالك استاذ ، شكد مرّح 😂💙
🙃🙃 thank you for helping me learn something usuf
The big question is, what do you do with leftover liquid. It still might contain quite a bit of the product, but, of course, if you concentrate it even more, there's a higher chance impurities will precipitate too. I wonder if there is a method (similar to distilling azeotropes) to repeatedly nudge the state when several solutes have maximal concentrations, so that on every second step either product or contaminants precipitate.
Yes, and that is the method that industrial precious metal recovery uses. They save the "slimes" until they have enough to be economical to process.
Sometimes the intended product like say gold, is still too low in concentration to recover, but silver is at 45%, so they extract the silver., but save the waste over and over until they can an appreciable amount of gold again.
Stirring rod or spatula?
glass stirring rod
Nice
How does one not blow up solvent when heating it up?
Blow up?
CHEM 2511 (Organic) online lab tomorrow yessir 😁
Fucking love your Intro man
And that’s how you cook crack Ladies and gentlemen !
No, crack is made by mixing cocaine with sodium bicarbonate in hot water and then evaporating all the water
@@isaackalashnikov3681wrong Ehen you do this method you will have the hole Salt in the free base !!! You use bicarbonite and Wait since the freebase Fall out and than throw the water away and dont evapoate it or use Ammoniak thats the purest Crack cokain But you should Wasch the Rest of Ammoniak out with water and the Street recept is to mix the coke powder with bicarbonate and but the dry powder into a microwave and Cook it thats dry cooking and you have more wight for the blackmarkwt because the hole bicarbonate Salt is in it 😂😂😂!
I'd like to ask you a question if the nickel sulfate crystal is dissolved with ethanol at a high temperature to remove the impurities. then how can we get the nickel sulfate crystal after that process?
Freeze precipitation
Greeting! Good video! Can I recrystallize potassium chlorate this way? Thank you
Yes, if you have the appropriate solvent. Assuming you used a double displacement method to convert the appropriate salt to the available chlorate, the salt will have a higher solubility than the chlorate corresponding to temperature. Typically heating to 100°C and cooling to 0°C twice twice while discarding the liquid each time will result a very pure chlorate because the chloride salt is that much more soluble in water that chlorates are.
Hello Professor
I want to ask
What is the recovery rate for benzoic acid when using 2.1 grams?
please reply
What is the recovery rate of 2.1 grams of benzoic acid? please reply
@@halaashraf2409 the recovery rate is approximately 2.754 weeks, one day after the blue moon, roughly 32 seconds before lunch time
Ahhhhhh the Meth Episode.... was wondering when you'd get around to this🤫😳🤯
Breaking bad (real)
He explains it in a very non meth way
I'm suck at recrystalitation, but good at Preperation.
By the way the video is helpful
Ah, It's 800th video!!
nice
hopes this helps me make thc-a
Helps with dmt too
Helps to make high purity bleach crystals from a bleach solution on hand, for storage and longevity of the now pure stable and solid form of Sodium Hypochlorite. My question would this make the sodium Hypochlorite crystals a salt base or HCL solid?
Hello sir I am from India
So...a NATURAL gemstone with inclusions can be recrystallized and become a clean gemstone?
If yes....what will be the teal difference between the natural stone BEFORE the process and AFTER the process?
After the process, can it still be called a NATURAL gemstone??
The composition. And... yes? I'm not sure.
Let's take quartz or Rudy (corundum) as an example. No, they would after the e process be considered lab grown or artificial, even if you dissolved naturally harvested components and used a seed crystal to kickstart the process.
The reason is because they were altered and remade in a lab.
Woooow 👏👏👏
If I recrystalize using solvent that dissolve my compound at room temperature, does it mean my crystal cannot get back after I recool at 0 degree celcius?
hmm, well it might, it just depends on the precise melting point, but it's not the ideal situation
So I just learnt how to make Crack Cocaine....
i'm confused by one part of this. Let's say you dissolve a solution with 50% product and 50% impurity, and perform recrystalization. What is preventing the impurity and product both forming cyrstals when you cool it down? If it did, then how would you seperate the two types of crystals in your beaker?
Impurities are highly soluble in solvent at room temperature so when recrystallization occurs they remain dissolved in solvent.
It only works if the impurities and product have very different properties. The impurity has to remain dissolved at the cooling temp (check its solubility) and the product has to have a way low solubility at that temp.
Take sugar and baking soda for example. Baking soda has low solubility compared to sugar. You can dissolve them both, but if there’s less than 2 grams of sugar per mL of water, it will remain in solution at room temp. Meanwhile, the baking soda will crystallize out of solution until the concentration hits 0.1 grams per mL of water. Of course, solubility increases with each solute added so keep that in mind and expect lower yields for bulk impurities.
Now take salt and baking soda for example. Their solubility is 0.35 g and 0.1 g per mL water respectively. You’d have to dilute between 0.1 and 0.35 g/mL to keep salt dissolved and baking soda hyper saturated. However, you’ll never be able to get more than 0.25 g of baking soda out per mL of water. And the closer to 0.35 g/mL you go, the more you risk getting salt in the mix. At the maximum scale, you’d only be able to get (1 - 0.1/0.35 *100)% or ~65% of your product (baking soda) out of solution. Whereas in the first example, you’d have (1 - 0.1/2 *100)% or ~95% of your product recovered
The crystals have a higher affinity toward themselves, meaning they push out impurities into the solution. Let's say that hypothetically you as you said have two solvates with exactly the same solubility properties in that solvent. The two crystals would grow apart from one another, but likely still be interlaced making separation by this method difficult. You would get grains of both products inside of one another and would have to find an alternative method. Thankfully no two chemicals have exactly the same properties and separation is still possible, even if it's a huge pain in the ass.
professor dave supremacy
อธิบายเกี่ยวกับเรื่องการกรอง
Filtering is a physical separation of products. At the point where you are ready to filter,, you have rendered either the intended product or the impurity as a solid that can be separated by a filter, screen, or some other physical process. This can also be just letting the solids settle to the bottom while pouring (decanting) the liquid.
I need in hindi language
Does this work for drugs?
First!
No 🤣
Where are you from?
لاالەالااللە
sweet now i can recrystallize my meth from powder to real crystals
What solvent u using?
@@god-8use isopropyl alcohol and add acetone to reduce solubility once its disolved with minimal isopropyl :-)
Hexane or heptane
How about naptha or denatured ethanol ?
Is it me or is he flexing his tattoo?
This ain’t materials science wtf bruh
This is organic chemistry.
Thank you sir
hi @Professor Dave. I really need your help. I have no idea how to study maths for IIT/JEE. Please start a playlist for that too just like you are doing for Chemistry. Plzzz sir. I have subscribed to all your 4 channels. You are amazing!!!!!!!!!
First!
Thanks sir
Hallo
@@zainrabee2675 yes
Where are you from?
hi @Professor Dave. I really need your help. I have no idea how to study maths for IIT/JEE. Please start a playlist for that too just like you are doing for Chemistry. Plzzz sir. I have subscribed to all your 4 channels. You are amazing!!!!!!!!!