Final answer:
Molecules with different structural formulas have different smells due to the variations in arrangements of atoms and functional groups. These differences determine how molecules interact with receptors in the nose, resulting in distinct smells.
Step-by-step explanation:
When molecules interact with your nose, they bind to specific receptors in your olfactory system. Different molecules have different shapes and functional groups that allow them to interact differently with these receptors, resulting in different smells.
For example, aldehydes and ketones often have fruity or sweet smells, while thiols have a strong, unpleasant odor resembling rotten eggs. The difference in smell comes from variations in the arrangement of atoms within the molecule and how they fit into the receptors in your nose.
Therefore, molecules with distinct structural formulas have different smells due to the various functional groups and arrangements of atoms, which determine their interactions with olfactory receptors.
Learn more about Molecules and their smells