Van Der Waals Forces

[MAHA493]

Thanks very much for the video is very helpful.

[littbballer24]

fluorine is just "F" not "FL"

[music1824]

you are a very good teacher thanks ! :p

[goldensilverstar]

why are there different forces ? cant it just be one force.....what the fuck man

[lazer1235]

@goldensilverstar LMAO

[TheGrotesqueReality]

What a great story about two rabbits (Van&Wallace) living in London and having a an affection for each other :)

[TheGrotesqueReality]

best thing on youtube is this channel

[vvaqasabbasi]

So What i understood about London Dispersion is that the position of valence electrons in any substance changes and they form slighly negative and slight positive charges at opposite ends! Then in turn due to electrostatic forces london dispersion is created between the substances! Like the forces that keep Graphite close! And also That London Dispersion is the weakest of Van Der Waal Forces! Please Correct me if i am wrong?

[mtlyul777]

Thanks your video helped me a lot!

[smitrib]

I love you.

[whiteapple1992]

Thank you very much for this video, it helped me clear things out about these things :D

[St3v3n947]

wow thank god for this video... i was so lost until now

[Abdullahtariq52]

upload a vedio on H Bonding

[ACDCafro1990]

I found this visual example very helpful. However i suggest you perhaps bullet point your ideas so you have a structure whilst talking so you don't back track as much.

Still thank you for this brilliant video.

[EvelynneSaysHi]

When I'm in distress, I run to Khan!

[fraglepuss]

Btw way the last 2 minutes sums it up sooo well

[ChuuChuuuUuu]

Im actually up to the 1p 1s or w/e in my chem class and not understanding because i missed a few classes, did you already go over that in a video?

[DanielHoward777]

Correct me if I'm wrong but didn't he do the

[ohayeson]

Not being a hater but in the video it was shown that Hydrogen was partially negative and Fl was partially positive, was it meant to be the other way round?

Class video, really helped me out! Thank you man :D

[quarkphotonect]

@ohayeson Haters gona hate! Lol just jokes! ya you are right, hydrogen is less electronegative than Fluorine, which is the most electronegative element

[bladdeins]

so good!

[dmm7203]

thumbs up for chemistry class



[sexylexy617]

@urockit2011 dude, it's pronounced "FAN-DER-VALLS" learn your stuff before you decide to be a smartass

[Iodine24]

Everyone trying to correct him, it's really getting annoying. HE'S AN AWESOME TEACHER!

[SidiKI96]

eyyy shut up besserwissers! khan academy roooocks! :)

[snehalnemade]

hey sir i m really in love with teaching method

[urockit2011]

thank you! van der Waals is pronounced like "VAN-DER-VALLS" by the way

[crucio6199]

Brilliant!



[medchemmb3]

What program do you use to draw these diagrams? Are you using a graphics tablet?

[canuckfanatic]

it was helpful, but would be more helpful if you didn't digress so much

[RTKL7]

wow! thanks, chemistry makes more sense now. However, I was wondering, in the noble gases bit at the start. Logically speaking doesn't it mean that the probability of electron being at a certain place at a certain time will change depending on the temperature? I'm confused. Thanks

[heartzheartzheartz]

thank you so much ! :D i understand it now

[sungirl761]

I just realized what it really means when my tutor says there is a london dispersion bond between Ar-Ar! ;)

[tejdeep125]

pure HCL(g) added to water is called hydrochloric acid[HCL(l)]. but pure HCL gas is called hydrogen chloride.

[ewokcell]

Great video, did a nice job of explaining it. Correct me if I'm wrong, but couldn't HCL be called Hydrochloric acid? (Hydrogen Chloride isn't incorrect, but usually binary ionic compounds involving hydrogen are called acids)

[punkrockzoie]

I'm not trying to draw a rabbit :)

[nabulsi826]

@punkrockzoie hes in fact draw a hand turkey with using his hand.

[Tomboy19942402]

van der waals

pronounced : van-der-vals

[loislai1996]

thanks!:)

[ClamatoJuiceify]

the whole f and fl thing gets me too. when you say it outlloud u expect it to translate to Fl instead of F. no bigs tho

[sl1pkn0t1100]

By the way, Fluoride is F not Fl

so HydrogenFluoride is HF not HFl

apart from that good job, it clarified things for me, thanks

[Shadowradio]

Seems like people claim to like your videos better than their science teachers. Maybe because you have their full attention and not all the distractions in the classroom. Also you make many errors. Difference between you and their science teacher as well.

[thisSreal]

@Shadowradio yeah he probably made some little errors, but the hole science is'nt wrong, i guess it was distraction F and Fl and the hydrogen positive negative, anyway i think he saved a lot of people for exams, btw....me too, thanks !!!

[TheGrotesqueReality]

grrrrrrrrrrrrreeeeeeeeeeeeeeea­aaaaaaaaaaat

[hippyrockar]

this is sooo helpful :D thanks

[as65807]

Youre better at teaching than my chemistry teacher smh -____-

[buenome]

ouuuuuuuuu i got the answerrrr THANKSS PPLE

[DelMonteMan243]

Thanks bro

[anglosaxon881]

I am a post bac and I watched all your videos to review for the MCATs! Thank you so so so so so much.

[VistarMonei]

4:59 Today, at this point in the lecture MY Chemistry teacher said that the guy who came up with the concept of London Dispersion Forces was "Jack London". It was a joke, but I don't think anyone else in my class really got it.

Ah, White Fang...

[Ivelion1]

How do I make the difference betweeen a hydrogen bond and a dipol-dipol bond? The bond between H2O molecules is a hydrogen bond or a DIPOL-dipol bond?

Thank you :D

PS : You rock !

[jmontis2]

@Ivelion1 good question, the difference is hydrogen bonding is limited to high electronegative atoms like O,N,F between H, and are about 10 times or more stronger than dipole dipole interactions from say, HCl and HCl, there simply isn't enough electronegativity to cause hydrogen bonding

[buenome]

@Ivelion1 loool thats my question aswell...let me kno if u get n anser..safee

[buenome]

HOW DO YOU KNOW THAT IT IS A HYDROGEN BOND OR JUST DIPOLE -DIPOLE>???????????

[grybok1ng]

@buenome hydrogen bonds occur between 2 molecules where each has a hydrogen atom paired with one of three super-electronegative atoms (F,O,N). Since the H is less electronegative than any, it hands its electron over to the F,O, or N atom, making that atom really negative since all the electrons chill with it instead of hydrogen. So, because of this.. the hydrogen bonds occur between a bunch of molecules of this type.. the positive hydrogen in one molecule attracts the negative side from another1

[buenome]

@grybok1ng iteee thanxx i got that bit and wa is dipole dipole than..??i dont undertsand the diiference ;/

[buenome]

@grybok1ng a kullllllll i gott itt..so its just btw FON and hydrogen ..when hydrogen bonding occurs..

SAFEEEE

[kury101]

you nutter

[liho123]

i love u.

[Cseal]

thank you for this video greatly helped :D

[xoxdhara2xox]

caan you use easy wordds, bcuz i still don't understand it.

D:

[runeseekerz]

This is very useful, i learned better than in my class. Thanks never stop posting these vids!!

[10sugarplum]

Omg thank you! I was struggling to get the concept for ages, lifesaver!

[mangohair123]

THAT WAS EXCELLENT THANK U SOO MUCH... PLZ TELL ME U TEACH I WANNA GO TO UR SCHOOL.

[tinaluvsbunny]

woww///thankkk u soo much

[joannecms72]

LOL! "i'm not trying to draw rabbit" Professor, you're so amusing in your own way, guess this is the reason why your lesson is getting so much interesting!

[TheTalking555]

nice video:) thanks for the insight:)

[TheX3Gamer]

Awesome video explaining this :D

I have a question, can you cover Alkanes, Alkenes and Alkynes like naming + reactions?

[hellokittydimaggio]

UR FRIGGGIN AWESOME :-}

[DyingElement]

I thought hydrogen bonds only occur when H is attached to F,O, or N...

[trojantactics]

well done

You make a good lecturer.

btw I am an engineering student from national university of singapore

[ozgunh]

This is grrrrrrrrreat! Can you make a video on introduction to quantum mechanics?

[burbua]

you are the sickest teacher. thanks alot for your help

[Cadmium77]

This is a superb series. Thank you so much...I can just drop in and have a taste of this stuff and it leads me on deeper and deeper into the subject.

[jayeshnikalje07]

wowwwwwww !!!!!! do u know what u hve done u hve melt iron .I hve never found chem to easy before.thaxxxx .can u becom my teacher plzzzzzzzzzzz.

[TheEpicFailMan]

Holly crap dude, if you could only be our teacher :(

[digemail]

Great video!, just embedded it on my website: nano dot ms.

Steve

[tfhkyoshi]

I wish you hadn't said that... Now all I see are rabbits instead of atoms...

[Manbearpig8900]

In one video, can you teach us how to draw bunnies?

[sloterfilmgroep]

Subscribed you are the best!!

[slaveworks]

Damn... neons are so happy....

its Hydrogen bond a van der waals force? i thought not....

[007natasja]

you have the voice of the female lamas with hats, constantly waiting for you to go carlllllllll but nice video

[winsonyeap94]

very nicely done indeed, easy to understand, even for a secondary student like me trying to learn about van der waals.

good job

[IcyNami]

Redo this video. There are too many errors when discussing hydrofluoric acid at the end.

[jffry102]

OMG you cant draw bunnies :D

thanks :P you really helped me to pass my chemistry test :D

Go on!

[loveleppard]

fluorine is F, not Fl

[drstingrae]

Good stuff, I am studying for the MCAT and these helps quickly reveiw!

[sara93916]

Wow you make it sound so simple!! Thanx aloottt <3

[ttlyADDICTED2BASS]

This guy is really good at explaining, he knows his shit.

Good video

[fuzegt]

You are a good case for there being a god.

[zackatpak101]

urrrrrrrrrrrrrrrrrrrrr awsumeeeeeeeeeeeeee

[wishing2fly]

this video explained much - i love it!! ur really good at explaining things :)

[labelleb21]

by the way your videos are amazing =] thanks a ton

[labelleb21]

v makes a fv weird sound =]

[labelleb21]

pronounced fan der vaal ...

[igknightus]

This also explaines why some women are more attracted to men then others...lol women are negitive naturally so us men being positive (depending on how much) we attract the girl ....who is less or more negitive...just depends on what molecule you need ")

[ladiesman21747]

yea its spelt van der waal but pronounced van der vaal.

[SumayahsIslam]

This is good, I have my A level chemistry exam in about 2 weeks time :S. Good luck all :)

[hermeskeil]

@nitinbansal2006:

unfortunately thats a mistake on his side.

It is actually F having a negative partial charge and H having a positive one. Though he was right on HCl.

[hermeskeil]

thank you very much

[gorgeousgoddess16]

thank you so much, hopefully i do well on my test tomorrow!!

[nitinbansal2006]

How come when you had HCL you had a partial negative charge on CL, and when you did HF, you had a partial negative charge on F?

[kal3idosc0pe]

@nitinbansal2006 b/c F and Cl are highly electronegative. They like to hog all the electrons when they're bonded to other atoms, so when you see them bonded to other atoms they have a partial negative charge.

[khanacademy]

@nitinbansal2006 The F should have been partially negative, just like the CL. Made annotations to fix the mistake. I don't know what I was thinking when I wrote partially + on the F side of the molecule.

[bsangoz]

@nitinbansal2006 because F is the more electronegative substance..

[talha318]

"im not trying to draw a rabbit" HAHAHA but yes great video man! Im reviewing for a test tomorrow and this is a GREAT review!

thanks alot!

[awet300]

thanks very much great video. we were able to catch yor mistakes from the things we learned from u lol

[tammythekool]

you should be my teacher!!!

[xpstkxps]

Isn't it F and not FL? And Hydrogen has a delta positive, not negative. Thanks for the great video, though.

[Divjot04]

@xpstkxps yup , F only

[HeaRTRiiPPeR]

At point 10:10, I think you got the delta charges the wrong way round. In H-Fl, isn't the Hydrogen end Delta-Positive, not Delta-Negative? And the Fluorine end Delta-Negative, not Delta-Positive?

[whats12345aa]

thats true, hydrogen end is delta positive.

[xingkai123]

yeah your right

[sandi0688]

you r right i think the same!! maybe he wrote wrong !!! but great video. H, positive; F negative

[marywaters7]

thanks great video extremely helpful for A-level chemistry! very informative!

[krithi256]

Thank you so much, a huge help :)

[captainjack77]

so what kind of forces would be present n acetic acid (CH3OOH) or Ethylbenzoate (C6H5COO2H5)?

[totallyobsessed19]

thanks for making theses videos, they are awesome. Way more detailed than what i need at the moment but it gives me a better understanding

[bodinian]

I'd hate to sound anal, but you wrote the Fluorine as having a partial positive when it has a partial negative. Please fix so I won't cry.

[WilesFilm]

fag

[bodinian]

At least I'm not a hater ;-)

[WilesFilm]

good point :)

[xogrind1]

Hydrogen bonding isn't explained very well in this video, the real reason why its so special is that the electronegativity of Flourine will strip away the last valence electron of Hydrogen which exposes it's protons which then creates a highly partial positive charge which will attract negative charges much better, no other element can do this which is why the hydrogen bond is so special.

[bodinian]

Hydrogen bonding doesn't need Fluorine to exist. It can be found in almost any substance with Hydrogen.

[xogrind1]

yea I was explaining just for his example

[bodinian]

Do you think more vids like this should be made? Im thinking about starting a series of info vids bc i tutor people at Temple and feel i can provide something

[xogrind1]

Oh yea definitly, vids like these are really great for visual learners like me, I can understand stuff much better when I see them like this video does instead of reading them which is how the school system teaches. To be posting vids like this is tapping into a huge market of students, infact this is one of the only vids on youtube to clearly explain london dispersion forces. Im sure the same can be said about many other high school level chemical Ideas, so you have your work cut out for you!!!

[SteroidsR4success]

@xogrind1 Thanks for the further explanation I didnt really understand at first the difference between the Hydrogen Bond and the Dipole Bond. So I mean basically all a Hydrogen Bond really is, is just a strong Dipole attraction?

[smoercleff]

these videos are great ! , i think there is mix up in the end , FL is supposed to be Negative and H is Positive

[sultanthewise]

why hydrogen is electronegative than fluorine??

[02280228]

I don't have to know all this for school or anything I just watch it because it's so easy to understand and very interesting!! thank you Sal so much for making these videos!!

[j00t00ber]

Ironically we had this in Chemistry today.

[infestor1]

cool