spectroscopy

Question 1

What is used as the standard reference for chemical shift measurements?

Answer 1

TMS , (CH3)4Si as it gives a chemical shift value of 0ppm.

Question 2

What is a deuterated solvent and give some examples.

Answer 2

Deuterium will produce no NMR signal in the frequency ranges of carbon and proton NMR.
CDCl3 is an example.

Question 3

What does an integration trace tell us?

Answer 3

The number of protons responsible for each peak.

Question 4

What can proton nmr tell us?

Answer 4

• The number of proton environments
• The relative number of each type of proton
• The number of non-equivalent protons adjacent

Question 5

How are hydroxyl and amino protons identified?

Answer 5

D2O will replace -NH and -OH with deuterium atoms causing the peak to disappear an signifying its presence

Question 6

What can a splitting pattern tell us?

Answer 6

The number of protons attached to the adjacent carbons.

Question 7

What do you need to know to find out a structure from the proton nmr data?

Answer 7

Relative peak area [ratio], ppm, splitting pattern, adjacent carbon, types of proton and analysis