NMR- Hydrogen and carbon enviroments

[soccerboi]

Hi guys, i'm confused about determining the number of hydrogen and carbon environments in NMR. (suggestions on how to improve/learn it would be great)
e.g something like CH3CH2CH2OH

CH2 s repeated so does that mean 3 carbon environments and 3 hydrogen environments or only 2?

I'm so confused about it especially when things are repeated such as the example above.
If possible could you guys provide some examples and explain how to identify the number of H and C environments.

Thanks so much!

[Bhootnike]

Hi guys, i'm confused about determining the number of hydrogen and carbon environments in NMR. (suggestions on how to improve/learn it would be great)
e.g something like CH3CH2CH2OH

CH2 s repeated so does that mean only 3 carbon environments and 3 hydrogen environments?

I'm so confused about it especially when things are repeated such as the example above.
If possible could you guys provide some examples and explain how to identify the number of H and C environments.

Thanks so much!

3 C, but 4 H!
i think that's right.. , but someone may wanna confirm that!

i just go by the rule that i draw a structural diagram and look at how many different ways C is bonded to elements and so i in simpler terms, just find the number of chemical enviroments based on the fact that 1 enviroment differs to another IF they arent consistent in their bonding.
so eg CH3 CH2 CH2 CH3
-firstly its symmetrical, so ignore 1 half. looking at just CH3CH2 shows that you have 2 different chemical enviroments for H and C.

[Reckoner]

Wouldn't there be three environments? The second CH₂ is bonded with an OH group, so would create another environment.

[thushan]

Hi guys, i'm confused about determining the number of hydrogen and carbon environments in NMR. (suggestions on how to improve/learn it would be great)
e.g something like CH3CH2CH2OH

CH2 s repeated so does that mean only 3 carbon environments and 3 hydrogen environments?

I'm so confused about it especially when things are repeated such as the example above.
If possible could you guys provide some examples and explain how to identify the number of H and C environments.

Thanks so much!

That molecule has 3 carbon environments, but 4 hydrogen environments!

Environments are just that - environments. Two H atoms are in the same environment if the carbon to which it's bonded is bonded to EXACTLY the same things!

Like say CH3CH2CH2OH - in the CH3...the C is bonded to a H, H, H and CH2CH2OH. carbon 3 is bonded to a CH3, H, H, and a CH2OH. carbon 2 is bonded to a CH3CH2, H, H and OH. The H on the hydroxy group is bonded to an O - different environment. So that's 4 H environments in total.

[TMlight]

3 Carbon environments. 4 Hydrogen Environments.

Let's take Hydrogen for example:
CH3 CH2 CH2 OH

The first CH3 is its own environment (it is the only one with three H's on a C atom.)
The first CH2 group is its own environment (the H atoms are on a C atom, with neighbors CH3 and CH2.)
The second CH2 group is its own environment (The H atoms are on a C atom, with neighbours CH2 and OH)- different from the other CH2 group!
The OH has its own chemical environment (its the only one with a H connected to an O atom.)

Thus 4 environments.

However if the molecule was CH3 CH2 CH2 CH3, there is 2 H environments. Why?

[Bhootnike]

However if the molecule was CH3 CH2 CH2 CH3, there is 2 H environments. Why?

so CH3 CH2 CH2 CH3
-firstly its symmetrical, so ignore 1 half. looking at just CH3CH2 shows that you have 2 different chemical enviroments for H and C.

 

[soccerboi]

Thanks for all the help guys
Also what about CH3CH3C=CCH3CH3 ?

I thought 1 carbon environment but apparently answer says 2.
And it would have 1 hydrogen environments right?

Edit: ignore this post

[Bhootnike]

Thanks for all the help guys
Also what about CH3CH3=CH3CH3 ?

I thought 1 carbon environment but apparently answer says 2.
And it would have 1 hydrogen environments right?

CH3CH3=CH3CH3 ?
is that even possible?!?

as in, second carbon has 2 C-H bonds, 1 c-c bond, and then a double bond? thats 5 bonds ? carbon takes 4 ?

edit. what i said is for ch3ch2=ch2ch3

so i have no idea how ch3ch3 works!

[soccerboi]

Oops nevermind i typed it wrong! and i figured it out. Sorry if i caused any confusion.