Question

Please show work for better understanding

13.9 Define coupling constant.

1. The distance between different signals
2. The distance between the peaks of a multiplet
3. The distance between the signal and the reference
4. The distance between the first signal and the
   last signal

13.20 Where do N–H signals appear

1. 1H NMR spectrum
2. 13C NMR spectrum
3. 1H and 13C NMR spectra
4. 1H, 13C, and DEPT spectra

13.17 Give the use of Distortionless Enhanced Polarization Transfer (DEPT).

a) Gives correlations between an 1H NMR spectrum and a 13C NMR spectrum.

b) Gives correlations between two 13C NMR spectra.

c) Gives correlations between two 1H NMR spectra.

d) Identifies the carbons in a 13C NMR spectrum as C, CH, CH2, or CH3.

13.18 List the type of peak seen in the DEPT-135 spectrum for a methylene

1. Positive peak
2. Negative peak
3. No peak
4. Two peak

13.19 In the DEPT spectrum, identify the group with a positive peak in DEPT-90
and DEPT-135.

1. Quaternary
2. Methine
3. Methylene
4. Methyl   

Answer 1