Markovnikov's rule and carbocations | Alkenes and Alkynes | Organic chemistry | Khan Academy

Courses on Khan Academy are always 100% free. Start practicing-and saving your progress-now: www.khanacadem...
Markovnikov's Rule and Carbocations. Figuring out which addition reaction is more likely. Created by Sal Khan.
Watch the next lesson: www.khanacadem...
Missed the previous lesson? www.khanacadem...
Organic Chemistry on Khan Academy: Carbon can form covalent bonds with itself and other elements to create a mind-boggling array of structures. In organic chemistry, we will learn about the reactions chemists use to synthesize crazy carbon based structures, as well as the analytical methods to characterize them. We will also think about how those reactions are occurring on a molecular level with reaction mechanisms. Simply put, organic chemistry is like building with molecular Legos. Let's make some beautiful organic molecules!
About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We've also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content.
For free. For everyone. Forever. #YouCanLearnAnything
Subscribe to Khan Academy’s Organic Chemistry channel: / channel
Subscribe to Khan Academy: www.youtube.co...

[@Antweezy]

Funny looking at comments from 6 years ago and suffering from the same things these people did.

[@jayrajsinghranawat4059]

1 year later from you i am also moving with same phase

[@MohamedaminAbdi-sm5uj]

Well,4 years after you nd here i am,Dealing with the same thing

[@AbdulKhaleed]

Skip to 5:45 for the Markovnikov's Rule explanation.

[@jiwachhetri4165]

Thanks

[@ts377]

thank dude

[@zayub1009]

Not all heroes wear capes

[@brianm.4368]

Interestingly enough, some wear thongs.

[@abdullaa.5088]

thanks

[@nopparats127]

I'm running out of words tanking you, please give this man a Nobel prize!!!!!!!! BEST TEACHER EVER

[@equitissingularis965]

Thanks, Bro- mopentane

[@MinhNguyen-wz2wn]

"For to him who has will more be given, and he will have abundance; but from him who has not, even what he has will be taken away" (Matthew 13,12 RSV).

[@goodandhappychristian3613]

Praise God you summed it up in a verse…Jesus is a,ways the answer!

[@MrColemoorman]

the hydrogens.....(starts drawing it)...thee hyyyydrogens (continues to draw it)

[@brettruss3359]

lmao im dying over here.

[@MUKnight73]

Your great man, thank you for simplifying and helping me understand chemistry.

[@dailygrind108]

Hey what are you doing now 9 years later

[@Bakedbread69]

this man and doctor stone are really amazing teachers

[@PulasthiKeragala]

Dr stone is my go to exam time entertainment

[@oliviaanna4282]

"the rich get richer"

[@sumiatheangel9397]

+oliviaanna42 *Bulls on Parade plays in the background*

[@Jenielle123450]

WOW I GENUINELY UNDERSTAND THIS NOW. Thank you so much!

[@YassinHM]

I always applaud at the end, brilliant!

[@FoSheezyMikeezyDoot]

I might just skip all my classes and just watch these videos!

[@jojogirl2008]

Thanks so much! I don't know what I would do without these videos! They are very helpful .

[@DC-ek3oo]

if my uni professor was half as good as you, I wouldn't be watching this while crying before my finals.

[@rsp1239]

Daylily Chen . Relatable

[@nehasiraj5106]

whatever i learnt from this video...i havent learnt that in one whole year!!!! hats off to this man

[@akashhera]

You explained it very clearly,I got it,even I'm not much familiar with organic chemistry,thanks a lot!

[@curtpiazza1688]

NOW I get it !! Thanx so much! 😊

[@boeing747200lr]

Sal, I am addicted to these videos.

[@sarafinamwaura6993]

Thanks 👍

[@ichaangl5154]

Thanks for helping me!

[@farry_physics4576]

Hello dear sir, the video after this one is titled as "private video", how can I watch it? please guide because I'm watching all the videos of your organic chemistry course in series and don't want to miss any. thank you!

[@Mmonira7]

OMG it has been ten years, and nowadays no know can teach better than khan academy

[@MonkeyDLuffy-xr4fl]

THANK YOU

[@Joole1000]

best voice ever! Lovely!

[@BunnyPoopCereal]

Amazing vid. All organic teachers should assign this video.

[@vanisood3140]

Beautiful explanation..u guys make things so easy... :)

[@kapilsharma7165]

The actual reason for Markovnikov's rule is hyperconjugation of alpha-hydrogens.

[@user-tv4lo9ch5v]

Have no idea what that means lol

[@syedsaadqainhaider2456]

Same no idea what he said

[@RoseGoldSkies5523]

I see the light.

[@jimobrien7129]

I nearly feel like dropping out, then watch your videos and think 'ah its not so bad ill stick around a tad longer'!

[@patrickcummins79]

this dude shud be man of the year

[@miriamramos8873]

Thank you so much for the visual explanations

[@vishal4928]

Watching in Octobers LAST WEEK 😂😂😂😂 After 10 years 😂😂

[@chimpy72]

@herpderpmonkey It's not about the bromine attaching itself, it's about the carbocation forming in the first place. If the molecule "feels" that the carbocation will not be stable, it doesn't form. The inductive effect of the CH2 groups lowers the energy difference between normal and carbocation states and thus encourages the molecule to lose the electron. The amount of negative charge pushed onto the carbon is not enough to blind bromine from seeing that positive charge though.

[@airdas]

Genial señor, thanks

[@quantum_psi]

Awesome! Thanks

[@dinornis]

(hopefully someone reads this) Does anyone know why the next few videos on the playlist are listed as private & whether you're missing out by missing those videos? Thanks :)

[@JustAnotherPerson3]

Hey, it's rly outdated but Morkovnikov goes with "o" :) And yes i speak Russian so i do know:)

[@JustAnotherPerson3]

Well after some research i think i need to apologize. Apparently it's an exclusion... (Or more precisely it's a rule that names don't have to follow spelling rules xD) It is actually Markovnikov after all.

[@tanmaysahoo7416]

You could have just edited your original comment but NO...

[@Chitario]

gotta respect his choice. not many people would choose this way these days :D

[@LThomasDPM]

Thank you so much!

[@emilybrown7302]

You should mention that the carbocations are stabilised by sigma conjugation which is the orthogonal overlap between the empty p orbital on the carbocations and a neighbouring carbon atom with electrons in filled CH sigma orbitals. The more carbons around it hence the more stabilisation interactions and so te tertiary is the most stable. Also there no talk of methyl cation species which are the least stable. It is expected that people discussing markovnikov rules would need the information up the level I have stated.

[@mohammedhassan2416]

Awesome it really helped me. I never used to get why the carbocation get more stable with more carbons naw i do. Thank you very much

[@snafoo131]

i hope they have this for orgo ii

[@Fiercely02]

Amazing! Thanks sir!!

[@slope560]

I feel like my brains about to explode

[@debasissahu5261]

Thanks Sal

[@s0m0c]

Gracias.

[@amin1583]

you are really great

[@Celeste-zs4yb]

Thanks!

[@TheLeily16]

I LOVE YOU !!!! Thank you !!

[@antoinesaury8862]

That rule would be explained just by inductive effect no ? I mean if you drew arrows explaining that on the molecule it'd be way more intuitive i think (with +I effect caused by 3carbon chain on the right & slightly delocating electrons on alkene).

[@buboykloots4369]

It can also be explained by the relative stability of a carbocation.

[@AishHumairaa]

thanks !!

[@saraaMoh]

I love you khan academy

[@gamefreak2050]

Couldn't you make the argument that because of sterics the bromine would want to attach to the first carbon?

[@kkkkkkkkkk955]

awesome! :)

[@sidewinder4489]

@n1a1s1i1m I believe the left one works because it has two carbon groups to stabilize the positively charged transition state whereas the one on the right doesn't work as well because it only has one carbon group. This means that the one on the left has a lower energy hurdle to jump over so it is more likely to occur. I'm not sure if that is what you mean? Either way, your post is a year old so you probably don't even care anymore.

[@Rizmaestro]

Quick question Sal (or anyone else): should Sal not draw a single arrowhead instead of ----> because ---> implies that there are two electrons being lost from an atom but in this mechanism we are seeing only one electron at a time being moved from one atom to anotehr. Anyone want to clarify this? thanks.

[@ITZSEEFO]

Thank you very much wallah u r bro ❤❤🙏

[@poojawolves370]

At 8:45 he says that secondary carbocation is more stable as it can borrow electrons from the electron rich molecules but since the electronegativity difference between carbons is 0,how can the secondary carbocation borrow electrons ??please someone help..

[@tra12345iscool]

@n1a1s1i1m A year later.. Its not bonded to a Cl, the point is that the H goes to the place where MOST of the H are bonded. The C-HH to make C-HHH. Or you can look at the carbons and see which one has the higher carbocation (In this case, it was secondary). We know carbon can have tertiary, secondary, and primary. In this example there is no tertiary so look at the secondary one.

[@kapilpudasaini5599]

so simple coz of u

[@demlafields1806]

can you use bond line structure on this video, please

[@barshakoirala5141]

helpful

[@SickACable]

So it's possible that we get 1-bromopropane, but more unlikely? In book I was reading it said that it's not possible to produce 1-bromopropane like that.

[@mf-hh8fk]

thank youu

[@mikevi76]

ty

[@UneasyTortoise]

is it always the case that the most stable carbo cation will also have one of the carbons with the most Hydrogens acquiring the other hydrogen?

[@kingo717]

Wait why is it that he draws the arrow from one carbon and attached the hydrogen to the other carbon? Can someone explain?

[@OnlyNeedJuan]

I have a question regarding methyl shifts. If you have a larger group (say CH2(CH3)2) would it be possible for this group to shift? Say it would turn a secondary carbocation into a tertiary carbocation.

[@manstett7066]

OnlyNeedJuan Gaming no only hydrogen and methyl groups can shift

[@MissMarleyLovesYou]

THANK YOU

[@jTraann]

what vid is before this?

[@phuthuy14101996]

Thank you very much just what I needed

[@potynaughty]

So, what I can see here is that the more stable the carbocation, the more it tendency to be bonded with H+, am I right? :\

[@heharshrajkamal8268]

is dule to inductive affect caused in secondry carbon

[@Forever1DFan100]

you are amazing :)

[@alainleroux8523]

Hi Mr Khan Can I please have the link for the private video. I Am busy with the whole series and would like to watch and make notes on all your Organic chemistry videos. Its video number 29.

[@saraaMoh]

so what if the secondary carbon is more stable? doesn't that mean it is less likely to react with other things? why is that needed?!

[@pakhtun7639]

ikr?!

[@santirulez]

Sarah M.T. It's saying that since the secondary carbocation is more stable, in a reaction, it will form the bond with Br much more often than the reaction where the primary carbocation bonds with the Br.

[@shrirangjoshi6981]

@Kash Army what about endothermic reactions

[@Ponnyboy555]

Markovnikov Rules

[@mohfa1806]

very nice videos...salute to khan academy....one question please : why the slightly positive hydrogen in HBR is attracted to the double bond precisely , why it is not attracted to any other single bond? ....thx

[@johannasky5696]

Because at the double there is an electron rich site, caused by the presence of the π electrons, since the partial hydrogen is an electrophile it will be attracted to it. The single bonds have no charge

[@mohfa1806]

Johanna Sky thank you very much for the reply...things are more clear now

[@adedejigenesis5223]

Are these really comments from a decade ago???? Wow Im here frustrated inhave to do this for the rest of my school years, dont know why i chose this course but oh well. This was helpful though

[@ovnisheeper6621]

yea "TANK" him a lot

[@Marksman2oo7]

markovnikov's rule starts at 5:50

[@charlesangelastro4499]

which video is the previous video?

[@sanguinemcorda4310]

I know I'm like a year late.. But go to the reaction mechanism playlist and you'll know :P :)

[@chimpy72]

@herpderpmonkey Not only that, but imagine: when the molecule takes the hydrogen, is it going to go for it from a carbon with an overall charge of 0 (neutral) or a carbon, let's say, with an overall charge of -0.01?

[@1SmokingLizard]

you got it all wrong, after the arrangements of the Hydrogen and Halogen, there are no more double bonds in the product. Try and rewatch the video and you see what happens to each segment at the electron sharing and bond breaking. Its tough but you can do it! Also, watch the case-sensitive when spelling out elements/compounds!

[@dasudheepthi8962]

cool

[@SamCableguy]

"Borrow electrons from some of its friends" HAHAHAHA

[@Rictoo]

@O0oSorousho0O Yes, when the valence shell is filled.

[@Kurmi83]

those rerepepetitions are kikikilling me.lol

[@MusicManCR7]

swiper no swiping

[@nthingplausible]

hi I would like to ask....Would the hydrogen still be attracted to the carbon with more hydrogen , if the ' group' was not the electron donating propane group but instead an electric withdrawing Halide ion? Would then change the stability of the carbocation right? Thereby affecting where the hydrogen bond first ? thanks in advance to anyone T.T

[@sumiatheangel9397]

+Lai Jing Wei It would still be attracted to the carbon with more hydrogen atoms. It doesn't matter whether it's a halide or a carbon chain--the main thing is that the carbon can 'borrow' negative charge off of those groups to stabilize its positive charge.

[@c0c0m0no]

Wouldn't they be constitutional isomers?

[@bfmvshinigami]

I love you even more. I'm Indian too btw xD

[@sonaljulania8974]

Shouldn't you have explained it with hyperconjugation and the number of alpha -H..

[@nishantkuamr2945]

thanks sir

[@ItsNeuroscience]

I love you

[@hanajb8317]

sory but what's the product ch3ch(ch3)ch=ch3 + hbr

[@nihayaturrohmah4230]

#27

[@BareClause]

I love you, Khan. I am AA, in y11 just starting Oc @side, have heaps of hw, will see this again when im done from this shit, wgm in a few months, i wonder who itll be, i can't wait, imglhsm

[@toka5188]

Thanks so much. can you make videos in Arabic ,bro

[@elishaflores5643]

Can you pls help me in doing my homework. Our professor isn't good😭 I WANT TO LEARN BUT I CANT UNDERSTAND THE LEASON😰

[@shadmanshakib5568]

😊😊