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## #1 2014-02-24 02:31:59

Agnishom
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From: Riemann Sphere
Registered: 2011-01-29
Posts: 21,748
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### 2-ethyl-3-methyl-hexane

How do you draw its structure?

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

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## #2 2014-02-24 05:47:53

bob bundy
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Registered: 2010-06-20
Posts: 7,056

### Re: 2-ethyl-3-methyl-hexane

hi Agnishom,

Well I thought I'd google this myself:

But there are several different diagrams here so which is correct, if any ?

I then did what I should have done to start with, and consulted the oracle.  She says this name is wrong, because the longest straight chain has 7 carbons, not 6.

Later I'll get her to clarify this, but there will be a delay.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #3 2014-02-24 08:36:22

bob bundy
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Registered: 2010-06-20
Posts: 7,056

### Re: 2-ethyl-3-methyl-hexane

OK here we go.

hexane => six carbons in a line:  C-C-C-C-C-C

Number them: C1-C2-C3-C4-C5-C6

2 ethyl means join an ethyl group onto C2  Hope this aligns properly:

C
|
C
|
C1-C2-C3-C4-C5-C6

Now stick a methyl onto C3

C
|
C
|
C1-C2-C3-C4-C5-C6
|
C

Now add Hs to bring all the Cs up to four 'joins'.  I'll leave that out as its trivial and will just overcomplicate matters.

But .... the name is determined by the longest carbon chain and there are 7 in a line*

C1
|
C2
|
C-C3-C4-C5-C6-C7
|
C

So it should be called 3,4 dimethyl heptane.

The oracle has spoken.

Bob

* Don't be put off by the carbons not being in a mathematical line.  They're not anyway.  The bonds are at approx. 109 degrees, so the diagram is sometimes shown zigzag.

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #4 2014-02-24 08:58:48

anonimnystefy
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From: Harlan's World
Registered: 2011-05-23
Posts: 15,937

### Re: 2-ethyl-3-methyl-hexane

A high-schooler with 3 years of chemistry can sure confirm that!

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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## #5 2014-02-24 09:22:41

bob bundy
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Registered: 2010-06-20
Posts: 7,056

### Re: 2-ethyl-3-methyl-hexane

Thank you Stefy, but a word of advice.

Obviously, it goes without saying that I'm always grateful to have your confirmation if I do a sum correctly.  But one thing you must learn ... it is never ...  ever ...  necessary to confirm the oracle's statements.  She who must be obeyed is always right.  Even when she is wrong.  Not that she is ... ever ... wrong, of course.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #6 2014-02-24 11:41:03

anonimnystefy
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From: Harlan's World
Registered: 2011-05-23
Posts: 15,937

### Re: 2-ethyl-3-methyl-hexane

Yes, that goes without saying.

Just, out of pure respect, should we be saying the Oracle?

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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## #7 2014-02-24 13:12:36

Agnishom
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From: Riemann Sphere
Registered: 2011-01-29
Posts: 21,748
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### Re: 2-ethyl-3-methyl-hexane

bob bundy wrote:

But .... the name is determined by the longest carbon chain and there are 7 in a line*

C1
|
C2
|
C-C3-C4-C5-C6-C7
|
C

So it should be called 3,4 dimethyl heptane.

Is there absolutely no way to draw 2-ethyl-3-methyl-hexane?

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

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## #8 2014-02-24 15:29:09

niharika_kumar
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From: Numeraland
Registered: 2013-02-12
Posts: 1,056

### Re: 2-ethyl-3-methyl-hexane

Agnishom wrote:

Is there absolutely no way to draw 2-ethyl-3-methyl-hexane?

the way bob drew the structure is right.
The actual structure will contain bonds at an angle which he mentioned as approx 109° but then we generally draw the structure of carbon compounds like the one made above.

friendship is tan 90°.

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## #9 2014-02-24 20:49:33

bob bundy
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Registered: 2010-06-20
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### Re: 2-ethyl-3-methyl-hexane

Agnishom wrote:

Is there absolutely no way to draw 2-ethyl-3-methyl-hexane?

A clever computer scientist decided to make the ultimate computer.  He built-in petabytes of memory, utilised a quantum computer module and multicore processors, used fibre optics for speed and an operating system that allowed the machine to learn when in use.  He gave it cameras to 'see',  voice recognition and speech.

Finally it was ready for use and he decided to have a small ceremony to mark the occasion.  He didn't smash a bottle, for that would have been a waste, but he did treat himself to a large glass of champagne.  "I name this machine 'The Ultimate Slave' ", he announced as he threw the switch into the ON position.

There was a crackle of electricity and in a flash, a high voltage spark fused the switch in the ON position.

"Good morning", said the machine; "but I think you've got the name wrong!"

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #10 2014-02-24 21:50:20

Agnishom
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From: Riemann Sphere
Registered: 2011-01-29
Posts: 21,748
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### Re: 2-ethyl-3-methyl-hexane

Sounds like a Frankenstein story, but what has it got to do with organic chemistry?

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

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## #11 2014-02-24 22:14:13

bob bundy
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Registered: 2010-06-20
Posts: 7,056

### Re: 2-ethyl-3-methyl-hexane

It's a parable.

Deliberately enigmatic, to encourage thinking.

In front of me is a chair.  I call it a chair; other people call it a chair.  But, if I decide to call it a flunge, is it still a chair?

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #12 2014-02-24 23:39:44

niharika_kumar
Member
From: Numeraland
Registered: 2013-02-12
Posts: 1,056

### Re: 2-ethyl-3-methyl-hexane

it will always be a chair for other people except you until you install changes in it because that is what they have been hearing from their childhood and changing that requires both a lot of time and effort.

but how can we imply this scenario in organic chemistry? do you mean that we can do something new to already defined rules for nomenclature?but it won't be acceptable as the rules which i have studied till now hold good for almost all situation and are revised well by chemists across the world.

pls. explain clearly if I have not got what you exactly meant to say.

friendship is tan 90°.

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## #13 2014-02-25 00:06:24

Agnishom
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From: Riemann Sphere
Registered: 2011-01-29
Posts: 21,748
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### Re: 2-ethyl-3-methyl-hexane

Did you mean: It does not matter what we call it.

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

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## #14 2014-02-25 00:12:06

bob bundy
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Registered: 2010-06-20
Posts: 7,056

### Re: 2-ethyl-3-methyl-hexane

All I was trying to say is that is the diagram whatever you call it.

My explanation started by constructing the diagram, then re-naming it correctly.  To answer this:

Is there absolutely no way to draw 2-ethyl-3-methyl-hexane?

Yes there is.  see that earlier post.  That's it.  There is no other way.

Does it matter what we call it?

The standard nomenclature is a way for everybody to use the same terms so there is no confusion.  You can use a different term but expect that people won't know what you're talking about.  If I persist in calling that thing in front of me a flunge, I must expect some strange looks.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #15 2014-02-25 02:16:32

Agnishom
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From: Riemann Sphere
Registered: 2011-01-29
Posts: 21,748
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### Re: 2-ethyl-3-methyl-hexane

bob bundy wrote:

All I was trying to say is that is the diagram whatever you call it.

That is what I was asking. Thanks to the Oracle

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

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## #16 2014-02-25 02:28:56

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 15,937

### Re: 2-ethyl-3-methyl-hexane

What's in a name? That which we call a rose by any other name would smell as sweet.

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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## #17 2014-02-25 04:41:11

bob bundy
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Registered: 2010-06-20
Posts: 7,056

### Re: 2-ethyl-3-methyl-hexane

Thanks, Stefy.

As ever, the Bard puts it better.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #18 2014-02-25 04:49:34

Agnishom
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From: Riemann Sphere
Registered: 2011-01-29
Posts: 21,748
Website

### Re: 2-ethyl-3-methyl-hexane

A name is important when you want to identify an object uniquely

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

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## #19 2014-02-25 16:57:27

niharika_kumar
Member
From: Numeraland
Registered: 2013-02-12
Posts: 1,056

### Re: 2-ethyl-3-methyl-hexane

yup.

friendship is tan 90°.

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