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Naming things with: Methyl and Ethyl whats the difference?

ok, so when naming hydrocarbons, how do you know when to put methyl and when to put ethyl?
I've been told that ethyl is one CH3 group...

what do u put when there are two CH3's coming off one C atom, but on different 'sides'.
and what do you put when there are two CH3's joined together coming off a C atom??

thanks

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Reply 1
Avatar for Holdo24
Holdo24
2
methy= 1 ch3 group
dimethyl= 2 ch3 groups on same C
ethyl= c2h5 group

methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl

Am I right?
Methyl=1 carbon chain branched off the parent alkane
Ethyl = 2 carbon chain branched off the parent alkane

If 2 methyl groups are presnet on different positions its di-methyl
Reply 3
Avatar for NoHands
NoHands
17
ch3 means methyl, even if there are 2 of them. c2h5 means ethyl.
Holdo24
methy= 1 ch3 group
dimethyl= 2 ch3 groups on same C
ethyl= c2h5 group

methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl

Am I right?


Yes
raspberryice
ok, so when naming hydrocarbons, how do you know when to put methyl and when to put ethyl?
I've been told that ethyl is one CH3 group...

what do u put when there are two CH3's coming off one C atom, but on different 'sides'.
and what do you put when there are two CH3's joined together coming off a C atom??

thanks


Methyl is just one CH3 group.
Ethyl is a -CH2-CH3 group.

If you have 2 CH3s coming off one carbon (ie 2 methyl groups) you number the carbon and then use that number twice, for example

2,2-dimethylhexane.

Would have 2 methyl groups on the second carbon along.

"and what do you put when there are two CH3's joined together coming off a C atom??"

I'm not sure what you mean by that?
Reply 6
Avatar for Holdo24
Holdo24
2
Loz17
Yes


:biggrin: Thankyou. (crashing Higher chemistry this year)
Holdo24
:biggrin: Thankyou. (crashing Higher chemistry this year)


Hehe

I'm failing A2 chemistry this year :p:

OP what you mean by "and what do you put when there are two CH3's joined together coming off a C atom??"??

Please expand
Reply 8
Avatar for raspberryice
raspberryice
OP
13
Loz17
Hehe

I'm failing A2 chemistry this year :p:

OP what you mean by "and what do you put when there are two CH3's joined together coming off a C atom??"??

Please expand


I meant 1 CH2, then CH3 in one branch. (attached to each other) sorry.
raspberryice
I meant 1 CH2, then CH3 in one branch. (attached to each other) sorry.


R−CH2CH3 R-CH_2CH_3 = Ethyl group
R−CH3 R-CH_3 = Methyl group
Adhavan
R−CH2CH3 R-CH_2CH_3 = Ethyl group
R−CH3 R-CH_3 = Methyl group


thanks....i'm nearly there...

soo
what is this?


4-ethyl 3-methylhexane??
raspberryice
4-ethyl 3-methylhexane??


Nearly: 3-ethyl-4-methylhexane
raspberryice
thanks....i'm nearly there...

soo
what is this?


4-ethyl 3-methylhexane??


:yep:

or 3-ethyl4-methylhexane (i think you're supposed to list them in alphabetical/number order but i don't think it matters that much at this stage)
EierVonSatan
Nearly: 3-ethyl-4-methylhexane


ah right thanks, so you go from the other end, because the ethyl is longer?

also, when u hav a cyclic hydrocarbon, and only one ethyl (CH2-CH3) thingy coming off it, how do u number it?

thanks a bunch everyone!
raspberryice
ah right thanks, so you go from the other end, because the ethyl is longer?


No it's because it has to be alphabetical order ethyl before methyl

also, when u hav a cyclic hydrocarbon, and only one ethyl (CH2-CH3) thingy coming off it, how do u number it?


If there is only one, it doesn't need a number :smile:
EierVonSatan
No it's because it has to be alphabetical order ethyl before methyl



If there is only one, it doesn't need a number :smile:


thank uuu:smile:

Something strange about chem..it can b hard at times, but i still enjoy it!
weird...
raspberryice
ok..
thank uuu:smile:

Something strange about chem..it can b hard at times, but i still enjoy it!
weird...


yeah, I have the same thoughts now :p:
Reply 17
Avatar for Oracle_163
Oracle_163
EierVonSatan
yeah, I have the same thoughts now :p:


eggs of...... satan......

this one is also an egg of satan
Oracle_163
eggs of...... satan......

this one is also an egg of satan


:lolwut:
Oracle_163
eggs of...... satan......

this one is also an egg of satan


urr...if u say so. :confused:

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