Question

a) The nicotine molecule is capable of making strong hydrogen bonds. Change nicotine into a different molecule, one that can no longer make any hydrogen bonds.

Answer 1

the main components of the nicotine molecule susceptible to hydrogen bonds are the nitrogens on the pyridine and pyrrole parts. So, what you might want to do is maybe add a halogen, such as bromine (since it's a weak hydrogen bonder). to prevent from bonding. since chlorine is a relatively larger halogen, it may be able to block interaction from a local hydrogen. Also, since you have nitrogen's, another option is to close the pyrrole and pyridine groups completely to remove the nitrogen and make it a cycloalkane.