I agree. That's why sometimes I prefer him over Sal Khan from Khan Academy. I think that you being able to see all his expressions makes it easier to know what's more important, what concepts relate to each other and to keep you focused.
this guy best explainer ever , he gets to the point and yet detailed but explains details in way 5 year old can understand and shows examples.. i appreciate u my good sir
I love this, when he used the marker and said the Br is coming out at you and when you rotate 180 degrees the bromine is going into the page everything about chirality just clicked. Bless up homie
Guess what, Dave (Professor Dave). Thanks to you I got the highest grade on my exam (we just got the results), and what's soo cool is that I'm the youngest in my class (studying at the university so some are 5-6 years older) and nobody got that grade but me, all thanks to you!
Thank you for visually explaining how enantiomers can't be superimposed! All other books/texts I referenced just said they were unsuperimposable, but never showed how like you did. I was confused... because my thinking was if I treated the image like a picture and just flipped it, it would superimpose, right? Thanks for showing me how it would work in 3-D space... makes complete sense now!
Woow I FOUND IT SO DIFFICULT TO UNDERSTAND THESE ORGANIC CHEMISTRY CONCEPTS. THANK YOU PROFESSOR DAVE. YOU ARE THE BEST SCIENCE TEACHER I HAVE SEEN. THANK YOU.
You are amazing!!!! Thank you for letting us use your videos for free because as students is hard to afford good explanations like yours!!!! you rock!!!!!!
Thank you kindly for gifting your knowledge! These 7 minute gems accomplish what 3 hours of Orgo from my teacher cannot- but- she does deserve some credit for turning me on to you!
This thing called Isomerism had been a real pain in the ass for me....thank goodness you, the Chemistry Jesus, exist that I'm no longer pulling my hair over this thing, which once ruined organic chemistry in school for me!!! Much love Professor !
You have explained very well . There were the basic concepts such as what's stereochemistry? What is chirality? What are structural isomers ? What is the stereogenic center? What are enantiomers? What do you mean by three dimensional way? It was a good lecture. Thank you ❤ You have given the nice examples to describe the super impossible or mirror images .
I am getting ready to teach a lot of organic students this concept and this video very beautifully visualized and conceptualized this topic. Very nice job Professor Dave :)
Thank you professor, I was really struggling while studying for the exam and this helped me a lot and the good thing it’s not a long vid so it saved me so much time ❤
But there is no restricted rotation right? For example, 5:28Why cant we just pull that br from inside the board plane to towards us plane?then it would be the same thing. Genuine doubt, because in geometrical isomerism, where there was a double bond in between, for say two carbon atoms, so cis and trans or syn and anti structures are not the same compounds and you cant rotate them as well cause the bond would break.
prof at 4:00 the molecule is not chiral, but if its mirror image is turned 180 degree the Br group will move behind and become wedge, wouldnt it be non superimposible now ?
It doesn't superimpose but the first rule is that if we can cut the molecule in symmetrical halves in any plane so we don't need to check the next rules.
super helpful and life saving!!! had a question- the achiral molecule at 6:35, I am not being able to superimpose the 180 degree flipped molecule with the main image.
Okay, can someone help? At 4:15, I thought the good Dr. say, "if you take the mirror image of the molecule it WOULD BE superposable. But the next example 4:48, he says the molecule with 2 carbon chain is NOT superposable BECAUSE THE Br would be PROJECTING "INTO" to board after rotation. WELL, in the 1st example a 4:15 that SAME Br is PROJECTING OUT of the board, Rotated 180 and that same Br at 4:15 is PROJECTED into the BOARD, just like the one at 4:48. So it too would not be superposable because Br would be projecting INTO the board and NOT out as it was before 180 rotation. What am I not seeing or understanding about superposable mirror imaging?
the mirror image may or not be superposable. if it is superposable, it's the same molecule, and is therefore achiral. if it is not superposable, then the mirror images are different molecules, and they are enantiomers of one another. for the first example, there is no reason to flip the molecule over, it is superposable precisely as it is, because of the symmetry in the molecule. in the second example we have to flip it over to get the carbon chain to line up, and then the bromine doesn't fit.
oKAY, thanks! I think I got it now! You might have said the exact same thing in the video, but either you used more words are not enough...lol!!! Or maybe I saw a fly as you were speaking. That's all it takes, ya know. But I did play it back 7 times...truly, thank you so much!
The only doubt I had was about the hand example if we take the mirror image of our hands and then rotate it 180° it will surely overlap then how could it fit as an example of an enantiomer?
My professor taught me that structures that only differ in bond (dash vs wedge) are the same molecules. At 5:05, you mentioned that the molecule with Bromine is an Enantiomer but the only difference is the Bromine changing from a dash bond to a wedge bond. Based what my professor said, wouldn't the two molecules just be identical? I don't mean to ask this in a condescending manner if its coming across that way. I truly am, just trying to understand the topic. Thanks!
yikes, your prof is super wrong! enantiomers are definitely not the same molecule, ask anyone who took thalidomide in the 50s. enantiomers are the same structurally, and have identical values for certain physical properties like boiling point and things like that, but they are stereoisomers, they differ in their 3D shape.
oh yes they are the same structurally in that all the connectivity is the same, but they differ in their spatial orientation, and to say that they are "the same molecule" is an egregious error!
Hello, one question, the bromine atom on the molecule that Professor is explaining on 4:16, is it not able to pass from the dash bond to the solid one when rotating its reflection?, and also, with the implied hydrogen atom, would that make it an enantiomer too?
No it won't there are a set of rules that one needs to check to see if those are enantiomers. First one needs to check the first rule and if the first rule says it not an enantiomer you don't need to continue and if says it is you continue and check all the rules relevant to it
Professor Dave, in that last example that had 2 F's, I understand that there is only 3 unique groups around instead of 4, which does not make it chiral. However, you said there is no way to rotate it so that its superimposable. Well, if you rotated 180 degrees, the OH will be dashed line instead of the triangle, and H was dashed but after the rotation of the mirror image, H is now sticking out with the solid triangle. This now looks different in 3D compared to the original. Am I wrong or is there a mistake here? Thank you prof you are a saviour!
well sure, it's a different perspective, but it's still the same molecule, you just turned it. but the more important point is that because it's achiral, its mirror image will also be exactly the same molecule.
Professor Dave Explains that is very true, it is like looking at it from the other side, it's still the molecule. I just realized that! Thanks a lot, and I especially appreciate the quick reply. You are the most underrated Orgo tutorial channel!
so two molecules are superposable if you put one over the other and every single atom of each molecule lines up perfectly, therefore making them identical molecules. if they can't do that, they aren't superposable.
Professor Dave Explains Yes perfect but I didn't get how to rotate ...if I rotate the image to superpose F ,the OH group gets dash bond and H gets Wedge bond right ?
I’ve got some FREE resources to help you ace OCHEM 1 this semester: chemmunity.info/dave
for some reason I like the fact that you actually appear in the video instead of just your voice. it makes it easier to learn and i dont know why
I think it's easier to focus when you can watch someone
I agree. That's why sometimes I prefer him over Sal Khan from Khan Academy.
I think that you being able to see all his expressions makes it easier to know what's more important, what concepts relate to each other and to keep you focused.
He looks like Jesus. Gives me hope for my grade
And he's handsome
@@NicholasCat you funny
this guy best explainer ever , he gets to the point and yet detailed but explains details in way 5 year old can understand and shows examples..
i appreciate u my good sir
please never stop making videos, they are way too helpful
I love this, when he used the marker and said the Br is coming out at you and when you rotate 180 degrees the bromine is going into the page everything about chirality just clicked. Bless up homie
Guess what, Dave (Professor Dave). Thanks to you I got the highest grade on my exam (we just got the results), and what's soo cool is that I'm the youngest in my class (studying at the university so some are 5-6 years older) and nobody got that grade but me, all thanks to you!
actually, you don't have anything to do with the other grades, it's just that I'm so happy that you explained everything so good!
woohoo! congratulations! happy to help.
+Professor Dave Explains thank you!
wow hope i could do the same thing for my stereochem exam this coming saturday xd
My professor at the university couldn't explain it to me for a whole year and you just did it in 7 minutes. King!
you explain so "flawlessly" professor dave...appreciate!!!
thank u chemistry jesus
Not funny
It is funny
@@firebloom02 ooow really I believe that u don't know nothing about jesus.. first try to understand k
@@debebeseyoum7081 I see you get easily offended. How abt a 🤣 emoji at you face
@@manikantan4809 ooow really... I m not easily offended but don't make the king compare with any one that's why I m being like this
Thank you for visually explaining how enantiomers can't be superimposed! All other books/texts I referenced just said they were unsuperimposable, but never showed how like you did. I was confused... because my thinking was if I treated the image like a picture and just flipped it, it would superimpose, right? Thanks for showing me how it would work in 3-D space... makes complete sense now!
You explain the stuff i think of and that no one somehow understands nor do I find them on youtube. Thank you
+Elizabeth Rey it's my great pleasure! feel free to email with questions.
Woow I FOUND IT SO DIFFICULT TO UNDERSTAND THESE ORGANIC CHEMISTRY CONCEPTS. THANK YOU PROFESSOR DAVE. YOU ARE THE BEST SCIENCE TEACHER I HAVE SEEN. THANK YOU.
8 whole years but this video is still helping lot's like me, absolutely genius...
his excellent communications skills and knowledge of chemistry, is quite attractive, lol..
Agree
The Law of Attraction does come to mind here.
-James.
Niggas tryna smash the teacher. Bro read
You are amazing!!!! Thank you for letting us use your videos for free because as students is hard to afford good explanations like yours!!!! you rock!!!!!!
I figured out in 3 mins of watching this, thank you Dave
I watched too many videos on YT to understand the concept but sir u are just amazinng!!!!
Thank you kindly for gifting your knowledge! These 7 minute gems accomplish what 3 hours of Orgo from my teacher cannot- but- she does deserve some credit for turning me on to you!
This thing called Isomerism had been a real pain in the ass for me....thank goodness you, the Chemistry Jesus, exist that I'm no longer pulling my hair over this thing, which once ruined organic chemistry in school for me!!!
Much love Professor !
What a legend, thank you. I'm going to watch all of your "organic chemistry" videoes :)
You have explained very well .
There were the basic concepts such as what's stereochemistry? What is chirality? What are structural isomers ? What is the stereogenic center? What are enantiomers? What do you mean by three dimensional way? It was a good lecture. Thank you ❤
You have given the nice examples to describe the super impossible or mirror images .
I am getting ready to teach a lot of organic students this concept and this video very beautifully visualized and conceptualized this topic. Very nice job Professor Dave :)
Professor Dave! You are amazing. Please keep making more and more videos. No one can explain like you!
My biochem proffesor did explain and I really never understood.. And this 12 mins I s a miracle. Thank you professor Dave
Nice explanation sir your handwriting is also nice.
thank you so much!!!!I had no clue when I first start seeing it!!! keep it up!!! I watch all your videos
Thank you professor, I was really struggling while studying for the exam and this helped me a lot and the good thing it’s not a long vid so it saved me so much time ❤
I am earning as a chemistry teacher enough money by watching your videos. Big Thanks to you 😊
I am from Ethiopia.Prof you explain it clearly. Thanks !
Perfect, that's how a professor teach chemistry in easy language 💯💯
Thanks Dave you're the best teacher ever
I cannot thank you enough for explaining organic chemistry!
The best professor for Biochemistry!
Thank u sir, your explanations are quiet simple. And had given a strong concept.
I like these videos better, than the ones where you just read the prepared lessons.
Perfect teacher, i understood everything, I hope to pass my organic chemistry exam tomorrow
perfect :)
I was going crazy as i couldn't understand it. but you helped me alot.
But there is no restricted rotation right? For example, 5:28Why cant we just pull that br from inside the board plane to towards us plane?then it would be the same thing.
Genuine doubt, because in geometrical isomerism, where there was a double bond in between, for say two carbon atoms, so cis and trans or syn and anti structures are not the same compounds and you cant rotate them as well cause the bond would break.
The key is just to pay attention to the wedges and dashes. Great explanation!
prof at 4:00 the molecule is not chiral, but if its mirror image is turned 180 degree the Br group will move behind and become wedge, wouldnt it be non superimposible now ?
i'm not sure what you mean
It doesn't superimpose but the first rule is that if we can cut the molecule in symmetrical halves in any plane so we don't need to check the next rules.
The intro alone was worth the like.
nice one professor... far more clear and better then my teacher...tankx
If u can explain optical isomerism ...
It would be so good I find it difficult to understand
These Organic collections are great!!
Really loved it!!
super helpful and life saving!!! had a question- the achiral molecule at 6:35, I am not being able to superimpose the 180 degree flipped molecule with the main image.
Really helpful! I had trouble understanding how that worked, but now I found it easier.
Okay, can someone help? At 4:15, I thought the good Dr. say, "if you take the mirror image of the molecule it WOULD BE
superposable. But the next example 4:48, he says the molecule with 2 carbon chain is NOT superposable BECAUSE THE
Br would be PROJECTING "INTO" to board after rotation. WELL, in the 1st example a 4:15 that SAME Br is PROJECTING
OUT of the board, Rotated 180 and that same Br at 4:15 is PROJECTED into the BOARD, just like the one at 4:48. So it too
would not be superposable because Br would be projecting INTO the board and NOT out as it was before 180 rotation.
What am I not seeing or understanding about superposable mirror imaging?
the mirror image may or not be superposable. if it is superposable, it's the same molecule, and is therefore achiral. if it is not superposable, then the mirror images are different molecules, and they are enantiomers of one another. for the first example, there is no reason to flip the molecule over, it is superposable precisely as it is, because of the symmetry in the molecule. in the second example we have to flip it over to get the carbon chain to line up, and then the bromine doesn't fit.
oKAY, thanks! I think I got it now! You might have said the exact same thing in the video, but
either you used more words are not enough...lol!!! Or maybe I saw a fly as you were speaking. That's
all it takes, ya know. But I did play it back 7 times...truly, thank you so much!
You save me🏋️. I will be taking my final exam for yr2 today and I have this module tonight! Thanks so much prof💯♥️👍🙏⬆️
best explainer ever
omg you're the best. I can't believe I finally understood this
The only doubt I had was about the hand example if we take the mirror image of our hands and then rotate it 180° it will surely overlap then how could it fit as an example of an enantiomer?
Thank you so much! This really helped me with my chemistry test! ❤
Thanks so much. This was helpful on my test!!
My GPA thanks you!
Straightforward explanation. God bless.
I was thinking of MDMA which has the wavy line doesn't that mean it's a racemix (racemate)? Have you got a video on that?
Would not hate it if you did a video on acid hydrolysis of an ester.
You are awesome, thank you for doing these videos.
My professor taught me that structures that only differ in bond (dash vs wedge) are the same molecules.
At 5:05, you mentioned that the molecule with Bromine is an Enantiomer but the only difference is the Bromine changing from a dash bond to a wedge bond. Based what my professor said, wouldn't the two molecules just be identical?
I don't mean to ask this in a condescending manner if its coming across that way. I truly am, just trying to understand the topic.
Thanks!
yikes, your prof is super wrong! enantiomers are definitely not the same molecule, ask anyone who took thalidomide in the 50s. enantiomers are the same structurally, and have identical values for certain physical properties like boiling point and things like that, but they are stereoisomers, they differ in their 3D shape.
He used it in the context of structural isomers. I'm assuming those rules do not apply for stereoisomers.
oh yes they are the same structurally in that all the connectivity is the same, but they differ in their spatial orientation, and to say that they are "the same molecule" is an egregious error!
Thank you!!!
So, can we deduce that at 5:39 , the enantiomeric compounds central Carbon is chiral?
only the one on the left with four different groups
Hello, one question, the bromine atom on the molecule that Professor is explaining on 4:16, is it not able to pass from the dash bond to the solid one when rotating its reflection?, and also, with the implied hydrogen atom, would that make it an enantiomer too?
No it won't there are a set of rules that one needs to check to see if those are enantiomers. First one needs to check the first rule and if the first rule says it not an enantiomer you don't need to continue and if says it is you continue and check all the rules relevant to it
I love this man!! he explains stuff so so so so well
I love you Professor David. You make chemistry looking easy!
Hi @Eni
You are saving my life professor
Thank you
THIS video worked like magic..
Appreciate!Very clear and flawless explanation!
your explanatiom helped me to understand easily
thank you Professor Dave
Just to let you know that I have been adding your videos to the Bibliography (APA format) in my O-Chem, Biochem and Anatomy reports :)
You are the REAL MVP
quality science right here
Professor Dave, in that last example that had 2 F's, I understand that there is only 3 unique groups around instead of 4, which does not make it chiral. However, you said there is no way to rotate it so that its superimposable. Well, if you rotated 180 degrees, the OH will be dashed line instead of the triangle, and H was dashed but after the rotation of the mirror image, H is now sticking out with the solid triangle. This now looks different in 3D compared to the original. Am I wrong or is there a mistake here? Thank you prof you are a saviour!
well sure, it's a different perspective, but it's still the same molecule, you just turned it. but the more important point is that because it's achiral, its mirror image will also be exactly the same molecule.
Professor Dave Explains that is very true, it is like looking at it from the other side, it's still the molecule. I just realized that! Thanks a lot, and I especially appreciate the quick reply. You are the most underrated Orgo tutorial channel!
Best explainer ever!!!!❤️❤️
At 5:34
Why the black line stuff turns to dashed points after flipping? What is the dashed points mean. I am quite confused...
Check out the first tutorial in the organic chemistry playlist to learn about wedge and dash bonds!
Professor Dave Explains thanks so much, I got it
Waiting, for you to reach over 1M subscribers
Super explanation ......
Not ME a Msc Biochemistry student fgrom Ghana on your page and understanding some concepts for the first time ever
Thanks Professor, you made it so simple :)
Your the man! Keep doing what you do.
the best explainer ever
Thank you so much Professor Dave!!!!!
God bless you. Ur knowledge was truly helpful.
just like you the video is so awesome
Thank you. You explained it very easily
Thank you, Professor Dave!
he is better than my college's professor
i love you,you are always helping me thank you so so so much
Thank you Sir!
Thank you professor Dev
You sir are a legend!!
You are the best professor ever!!! Thank you ❤️
Thank you so much, Prof. Dave!!! Long live!!!
I have a doubt
What are super imposable and non super imposable molecules..?
Pls someone tell
so two molecules are superposable if you put one over the other and every single atom of each molecule lines up perfectly, therefore making them identical molecules. if they can't do that, they aren't superposable.
At 3.09 you turn it and the z swaps places ?
So would enantiopure mean it lines up correctly? Or is that a totally different thing
So helpful!
Really Helpful!!!!
What is B.pt 60° and m.pt-80° of cis-1,2 dicloroethene
6:20 . I didnt get hows that superposable...I tried but couldnt find a way to make it superposable by rotating it 180`
you have to get the mirror image first, then put the mirror image on the original. because there are two identical atoms, you'll be able to do it.
Professor Dave Explains Yes perfect but I didn't get how to rotate ...if I rotate the image to superpose F ,the OH group gets dash bond and H gets Wedge bond right ?
so then spin it so that you swap the position of the two fluorines. then it will work.
Professor Dave Explains thank you professor ! Will work it out
So good at explaining! Thank you!
he is a good explainer
Can anyone plz make the mirror image of last compound having( 2 fluorine ) & then rotate 180 degree & try to superimpose