Be Careful guys, the last one is wrong. He should count the carbons on the parent chain starting on the left end for this one. It's different from the second one and he should have started over, not just kept the names of substituents he had from the 2nd one.

@cheezepizza1

8 жыл бұрын

hey could you explain what you meant? I'm just starting to understand O.Chem.....

@berserker955

8 жыл бұрын

for the last example he kept counting from the right even though he should've started from the left because the priority has shifted due to the new propyl group added (you wanna always start counting from teh side that will give you the lowest number corresponding to your largest functional group, in this case propyl). By that logic I think it should be called 5,6 diethyl - 5isopropyl decane. hope that helps.

@annodomino9285

7 жыл бұрын

yas incorrect example

"let's draw something crazy here" lol

i learned more in the first 3 mins of this video than in 50 mins of my chem class. thank you so much!!

7:54 I would call this 5,6-diethyl-5-(1-methylethyl)-decane

@sotharithsar9767

10 жыл бұрын

I'm sure 5,6-diethyl-6-(1-methylethyl)-decane is wrong for IUPAC. But 5,6-diethyl-5-(1-methylethyl)-decane or 5,6-diethyl-5-(1-methylethyl)decane?

@BrianStephenAquinoDomingo

9 жыл бұрын

You are definitely right!

@tmtanzimtmmt1598

4 жыл бұрын

This is right i think

I haven't even learnt this complexed organic chemistry in school yet- will probably do so next year- and I'd be willing to bet right now that it won't be anywhere near as interesting- or dare I say, as fun- as your lessons! The past hour or so has just flown away watching these videos, fantastic work!

No, when you pick the numbers, all have to be relative to the same side of the chain. 5 means that they are linked to the 5th carbon of the chain, and we don't have 3 groups linked to the 5th carbon in the main chain, but 2 groups (1 ethyl and 1 isopropyl) to the 5th carbon and 1 group (1 ethyl) to the 6th carbon.

I don't understand anything in my Vietnamese workbook, but I learn a lot from your videos

7:13 It's a mistake that the prefixes don't matter. Prefixes like "iso" are part from the names, so "isopropyl" will start with an "i". Prefixes like "sec" are not part in the name, so "sec-propyl" will actually start with a "p". If there's a hexane with a methyl on 2nd and an isopropyl on 3rd carbon atom, the name will be either "3-isopropyl-2-methylhexane" or "2-methyl-3-secpropylhexane". So, the prefixes matter.

@computerlover9290

2 жыл бұрын

Where do you know this from?like in which book is this written?

Your multicolored videos are so cool. So easy to follow along rather than reading my big fat ochem text over and over again. Thanks so much!

My god, can’t express ma gratitude, and the best part is.. IM NOT EVEN FROM THIS SYLLABUS AND I STILL UNDERSTOOD!!!!!!!!!

instead of 5,6-diethyl-6-(1-methylethyl)-decane, could you also name it 5,6-diethyl-5-(1-methylethyl)-decane? because you can also number it from left to right

these colors and your soothing voice are getting me through finals

@sulimanshams4734

4 жыл бұрын

How were your finals?

Old is gold 7 years old video and it is gold thanks so much

excellent presentation!, thank you

YOU ARE A LIFESAVER. had straight A's in all of my classes all year, but this 4th quarter my chem and algebra 2 grades dropped to C's and you have helped me get them to A's again before finals. THANK YOU SO MUCH! IT WOULDN'T HAVE BEEN POSSIBLE WITHOUT YOU.

@learningcommunist5502

Жыл бұрын

BETTER GET STRAIGHT A's ALL THE TIME OR WE WILL SEND YOU TO THE GULAG!!!

@learningcommunist5502

Жыл бұрын

or Stolypin's Necktie

Could someone explain why it isn't sec-propyl and why is it iso-propyl? Because it attaches to 2 carbons from the backbone chain so I thought it would be sec.

@siddelaramadevi7465

2 жыл бұрын

Bcoz it gives uh iso propyl bcoz it have the shape L So called by name iso propyl

@azyle2104

2 жыл бұрын

I also don't understand

This was so helpful!!!! Thank you!!!

The train of thought in naming in chemistry makes so much sense.

@Jessicaaljp That explains a lot, thank you so much. I have a followup question though, if a structure is butyl (or anything greater than propyl) what arrangement would differentiate isobutyl from sec-butyl?

"Sec-propyl does not exist, the smallest sec- substituent is sec-butyl. If you apply the meaning of "sec" to draw sec-propyl, you will see that it is exactly the same as isopropyl, the preferred name." - Bing

Great videos and videos/channel/organization all around ( I love Khan Academy :) ). I like to revisit organic chemistry from time to time... cause I'm crazy LOL. But two errors I believe. On the last example, 1) I believe the numbering should be reversed as to give you the lowest number with the largest/bulkiest substituent. So 5 should be for the ethyl and isopropyl, and 6 should be for the lone ethyl 2) From what I remember and gathered through a quick google search to try and confirm, isnt "iso" one of the few terms that IS included in the alphabetical order? Sec, tert, di, tri, etc., are all not considered when naming and determining alphabetical order, but I believe iso is. Is that in accordance with IUPAC?

dude you help me more at school with this videos of chemistry than my teachers. Thanks (;

thank you yyou are my savior. i have a final tomorrow and i did not understand any of this. but now i do. THANK YOU.

very worth, thanks for adding...pls add more like these..love to learn

You are very helpful Comrade

I like it..good job

You made a really confusing lesson become so much easier... Thanks!!!!!!!!!!!!

There are two ethyl groups, and either can be the sixth or fifth group if they are the only substituents. However, since iso-propyl exists, it must also be taken into consideration in order to have the lowest numbers possible, so the carbon attached to both the ethyl and the iso-propyl group will be the lower number, in this case five.

Awesome, thanks for posting!

Thanks sal sir! I didn't know you did good chemistry vids too!

i love you! just made o chem so much easier!

Hi, Khanacademy, would the last example be 5,6-diethyl-5-1-methylethyldecane?? Also, I have a question, when you use the alphabetic rule for methylethyl, is it the "meth-" that counts or the "eth-" that counts? would the methyl be considered as just a branch on the carboxyl group?

THANK YOUUUU I WAS DYING AND NOW I FINALLY UNDERSTAND

you are great thanks alot

You are a real hero. God bless you. Can you please upload some stuff about Analytical chemistry.

thank uuuuuuuuu very much for helping me with my lessons

Great!

The answer to the last example is wrong but it made me review and practice my recently acquired knowledge.

I LOVE YOU THANKYOU FOR SAVING MY LIFE

shudnt the IUPAC name be 5,6 diethyl - 5isopropyl decane.. please ensure that the answer is right.

@sesshysayoyasha93

8 жыл бұрын

+AMAL K B Isopropyl is in the sixth spot, not the fifth @.@

@patrickcorcoran8183

8 жыл бұрын

+Wen Rio But you should always number from the direction closest to the end of the chain, which in this case would be 5 (going from the left)

@annodomino9285

7 жыл бұрын

amal you are correct khan academy is incorrect!

@lawyerhomeland3261

7 жыл бұрын

You should see that there is another alkyl group going from the right.. In that case, khan is right!! What do you say about that??

@chriscastiello5812

6 жыл бұрын

You should use the lowest numbers as possible as you can. So he should've number the structure from the left (5,6,5 < 5,6,6)

I agree with mattness20 - you have to reverse the direction of numbering the parent group in the last example because then arrive at more subsituents sooner.

Loved the ending though, made me laugh. :)

Just my 2 cents; First off, I like to start off by saying you are a great teacher, and no other can be like you to teach chemistry, but in this particular episode or chapter, I didn't like how the molecules were visually structured. If the carbons were shown as C - C - C etc, it would have been much easier to understand, especially the complicated molecules. But I did learn so thanks you!

You can start counting from either end, It doesn't matter, what matters is that the sum of the numbers indicating the chains is the lowest possible. 5+6+5 is lower than the 5+6+6 proposed by the video.

its all good, I love learning man!

Can you compile the Organic stuff into an Apple App like you did for the others! I love your videos!

wow this is very helpful

@TheInterNGA Find the longest carbon chain, select the best side(which makes numbers in the naming as small as possible), and count from only the selected side . In my opinion, the last one should be 5,6-diethyl-"5"-isopropyldecane instead of 5,6-diethyl-"6"-isopropyldecane. If you count from the left, the numbers will be smaller, which is the rule of organic chemistry naming.

how do you determine that isopropyl has preference over diethyl to start numbering the other way around?

THANK YOU SO MUCH

Brilliant name. Just brilliant! :D

Question... What software/hardware do you use to make these videos? they are great btw!

There's a small mistake here. Adding the isopropyl group onto the 6th carbon from the last molecule is incorrect, because you label the carbons so that the substituents are on the lowest carbons. So adding it there would cause the carbons to be labeled from the opposite direction, giving two substituents on the 5th carbon and one on the 6th carbon, instead of the other way around. Final systematic name would then be 5,6-diethyl-5-isopropyldecane. :)

It can be 5,6- dimethyl 5-(1methyl ethyl decane? It is the same?

how do you know which side to start counting the carbon chain? because when i googled the structures of other organic molecules, it started from the left. does it matter?

At around 2:50, when you introduce the second Ethyl group, you still count from the right hand side to remain consistent? (It'd be the 5th carbon if you counted from the left, which is less than 6. But then you'd have 5,5 diethyl decane - which seems inconsistent.) If someone could clear this up for me and confirm/deny my thinking that'd be great, especially for when harder examples come up; i.e. the next video. :D

U R awesome

I HAVE A QUESTION!Can we attach the smaller chain of carbon atoms to either ends of the longer chain? Or does it only have to be in the middle? Please answer and thanks for the awesome video! Chemistry was never so easy :D

@Purp1eMonkey Methyl has only ONE Carbon attatched to the Parent Hydrocarbon (-CH3) and Ethyl has TWO Carbons attatched to the Parent Hydrocarbon (-CH3-CH2). Just add the prefixes that fit accordingly to -yl (Like 3 C's = "Propyl", 4 C's = Butyl, 5 C's = Pentyl, etc.)

Thank you so much!!!!!!!!

Shouldn't it be 6( 1-methylethyl ) 5,6-diethyl decane

well explained

Why is the 6-isopropyl group at the end of the video not a 6-secpropyl group? Since the 1 carbon is attached to two carbons?

@jsfang407

8 жыл бұрын

+Matt Maxwell see 4:01

Thanks man ^^ Ur awesome! ps, you said 5,6-diethyl-6-isopropyldecane but can you also write 5,6-diethyl-5-isopropyldecane? because the isopropyl is closer to the beginning that way?

I have a question at 3:07 it is not more => 5,5-diethyldecane because we should take the lowest chain on the back bone so ... I'm not sure at all, does someone have the answer ?

@kevingadacho2524

8 жыл бұрын

+SwT Nahaax it is because he started counting at the right parent chain hence he cannot start counting again at another end/start of the parent chain.

What happen to the ethyl group attached to the 6th carbon? Shouldn't we include that in our naming too? Thank you!

If there’s more than one -(1-methyl ethyl) How to name, please?

My teacher has told us that when numbering you should always attempt to provide the lowest numbers possible. Is this correct or is the topic trival? because if it isn't wouldn't the structure be named 5,6 - diethyl 6 - isopropyl decane?

This should be 5,6-Diethyl-5-(1-methylethyl)-decane. It's 5-(1-methylethyl) because there's 2 groups on the 6 and 1 group on 5, so you count left to right this time, 6 is 5 and 5 is 6. You could go either way with 5,6-diethyl and count only right to left for the 5-ethyl. (hope that's correct)

@WashWashRevoluti0n

7 жыл бұрын

Kristopher Cordova yeah I agree with you, but I think he didn't try to confuse everyone since he initially was writing a common name anyway and he only changed the 6isopropyl for the sake of systematic naming. If he named that diagram from scratch, what you said is right in my opinion

8:10 So to make it even more confusing, Chemistry will mix combine Common and Systematic naming in one compound name?

i think the prefixes ( iso,sec and tert ) for common naming ... he used the systematic naming in the example of 5,6-ethyl 6-(1-methyl ethyl ) decane ... but this is wrong too . it should be 5,6-ethyl 5-(1-methyl ethyl ) decane ...

@alext9067

5 жыл бұрын

Methyl ethyl is not in alphabetical order. Why?

I think in the 3rd example It would be 5,6-diethyl-5-isopropyl decane 5+6+5=16 In the answer you have written 5+6+6=17 I think the lower number should be written

@jc63921

9 жыл бұрын

Anas Osama No, i think your wrong because the isopropyl group is not on the fifth carbon chain...

@anasos1996

9 жыл бұрын

John C I think the isopropyl group is on carbon 6

@jc63921

9 жыл бұрын

Yes, which makes the answer 5,6-diethyl-6-isopropyl decane

@anasos1996

9 жыл бұрын

John C Sorry, I mean on carbon 5 Begin numbering from the left side

is IUPAC the common or systematic scheme?

you saved my life

Wait, shouldnt it be 5,6-diethyl-5-isopropyldecane, as we can count from the left?

Your logic seems right to me, but shouldn't you maintain consistency by using the same chain order? if it was 5-isopropyl instead of 6, he would have to count from the other direction, but then it would be inconsistent. I'm just a student, so I may not be correct, but can someone pls clarify this?

the last molecule should be named: 5,6-diethyl-5-isopropyl the numbering should start from the left --> get lower numbers

with the last one, shouldnt you count for the other end so its 5,6-diethyl 5-isopropyl decane... so the numbers added together are as low as possible?

how do you know if its methyl or ethyl???

How can the 1-methylethyl group be called sec-propyl and also iso-propyl? Shouldnt it be sec-propyl as the adjoining carbon to the backbone is joined to two other carbons and not one?

That's not what they were saying. You're not switching during the naming. It's just that if you start from the other end, you have two groups on the 5th carbon and one on the 6th rather than vice versa, and so in total the sum is smaller (5+5+6 < 5+6+6).

i have a question. that part about the five six diethyldecane, why is it 6, when from the other side it is 5? why didnt we say 5,5 diethyldecane?

his last sentence was epic

Yeah I was wondering the same thing haha.

Is there another useful method to find out Structural formula :) I need help and I don't understand.

@Chemmmn It's a completely new section

Will there a be a new category for Organic Chemistry or under chemistry for your website? I could not find it under the chemistry section.

Why can't we write 1-methylethyl as 2-propyl such that the propyl group is attached to main chain via it's 2nd carbon?

Hi, great video once again! one thing - isn't 1-methylethyl or 1-ethylmethyl just the same as methylethyl or ethylmethyl as either way it will be attached to the 1st carbon?

@koonagueroagnis8174

7 жыл бұрын

Nope, smaller group goes first so its methylethyl.

no use calling the group (1-etylmetyl) cuz if it was connected to 2. carbon it would be propyl group already.

what software you're using

Is it ever too late to change to an Arts Major?

Shouldn't the last 8:18 molecule be called 5,6-diethyl-5-isopropyldecane, so that the number will be the lowest?

no even if u number the other way its still comes out to be 5,6- diethyl decane

i like to think of the branck groups as substituients??

I'm sure some people are learning this by reading their textbook over and over until their eyes pop out. I, on the other hand, can sit back and enjoy while eating some ice cream while I learn organic chemistry! :D

@temitopenlewemchi7461

3 жыл бұрын

How are you so cool about this 😩...How do you do it?

Hmm, how do you figure? I'm still getting 5,6-diethyldecane with identifying the longest, most continuous Carbon chain with the most substituents.

could someone help me out here, the iso propyl and iso butyl look exactly the same at 5:07, please help

where do ethyl methyl came from?

I got it now, but thank you anyway. :)