F324: Module 3: Carbon 13 NMR

Question 1

I) What does the number of peaks tell you on a C13 NMR spectrum?

Answer 1

The number of chemically different carbon atoms present.

Question 2

I) What does the value of the chemical shift in ppm tell you on a C13 NMR spectrum?

Answer 2

The chemical environment of the carbon.

Question 3

I) What does the size of the peak on an NMR spectrum tell you about the carbon.

Answer 3

Nothing (at A-level) since it doesn’t correspond to the relative number of equivalent carbon atoms like it does in proton NMR.

Question 4

I) Do splittings occur with C13 NMR?

Answer 4

NO

Question 5

I) What are the two main factors to look at in a C13 spectra?

Answer 5

The Number of Peaks

The chemical shift of the peaks