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Help spectroscopy

Help I don’t get why it’s 3 peaks isn’t it 2 because there’s 2 carbon environments the A’s labelled are all the same and the B in the middle so 2 c environments right??IMG_2531.jpeg
For the bottom Q ignore the top
(edited 1 year ago)
Original post by Alevelhelp.1
Help I don’t get why it’s 3 peaks isn’t it 2 because there’s 2 carbon environments the A’s labelled are all the same and the B in the middle so 2 c environments right??IMG_2531.jpeg
For the bottom Q ignore the top

2,2-dimethylpropane should only have 2 peaks on the 13C nmr spectrum for exactly the reasons you have posted.

I suspect there was a typo on the answer sheet (that, or they included the TMS peak, which they shouldn’t have and don’t appear to have done for the other molecule).
Original post by TypicalNerd
2,2-dimethylpropane should only have 2 peaks on the 13C nmr spectrum for exactly the reasons you have posted.

I suspect there was a typo on the answer sheet (that, or they included the TMS peak, which they shouldn’t have and don’t appear to have done for the other molecule).


Tysm!!
also this q I don’t get how proton b is 3-4.2 ppm
because it just CH so would it not be 0.5-2.0ppm
using the tableIMG_2532.jpeg even for the q6 i don’t get it 😭 plz help
(edited 1 year ago)
Original post by Alevelhelp.1
Tysm!!
also this q I don’t get how proton b is 3-4.2 ppm
because it just CH so would it not be 0.5-2.0ppm
using the tableIMG_2532.jpeg even for the q6 i don’t get it 😭 plz help


It also has a CHO group next to it, so really it is a CH-C=O environment as opposed to just a CH. The CHO group contains a highly electronegative oxygen atom that increases the shift on the adjacent CH.

Edit: I looked at the wrong molecule, but a similar principle applies. There is an oxygen bonded directly to the CH, so it’s a CH-O environment.
(edited 1 year ago)

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