It can be seen that the three methyl groups in camphor and isoborneol show up as separate peaks, whereas those in borneol overlap to where they almost appear as a single peak. Based on your knowledge of chemical shift factors, explain why this is so?

isoborneol and camphor both have methyl groups that have different shielding zones with -OH and -C=O groups respectively.

Explanation:

Using the knowledge of chemical shift we can see that out of the three methyl groups in isoborneol, there are two methyl groups that are not influenced by the chemical Influence of the -OH functional group while one of the methyl groups is influenced by the -OH functional group.

For Camphor, two out of the three methyl groups are in shielding zones of the Carbonyl group, -C=O. While the last of the three methyl groups is out of the shielding zones of Carbonyl group, -C=O.